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Which is best -V8 or V6? by Dennis LaGrua
Started on: 05-04-2007 11:03 PM
Replies: 93
Last post by: vinny on 07-30-2008 11:36 PM
Dennis LaGrua
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Report this Post05-04-2007 11:03 PM Click Here to See the Profile for Dennis LaGruaSend a Private Message to Dennis LaGruaDirect Link to This Post
I started this post to take a fair minded look at the benefits of using an efficent, lightweight, modern, economical V6 engine in your Fiero as opposed to using an expensive heavy inefficient gas hungry V8 engine. In todays times we have cars with 4 and 6 cylinder engines running the 1/4 mile in the 8 and 9 second brackets so it seems that the V6 wins on all counts. What's your preference and why?

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Report this Post05-04-2007 11:18 PM Click Here to See the Profile for fieroluvSend a Private Message to fieroluvDirect Link to This Post
Honestly this thread is going to cause one heck of a flame war. But to answer your question it's all a matter of preference. Me personally I would say V6 just because of the economical standpoint of it and still get decent performance. The best of both worlds so to speak. I use to be a firm believer of there is no replacement for displacement, it is just not so anymore. And not to mention how hard it is to find a trans for our cars that can handle the high horsepower and Torque of a beefed up V8.
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Report this Post05-04-2007 11:35 PM Click Here to See the Profile for FieroMonkeySend a Private Message to FieroMonkeyDirect Link to This Post
can someone pass me some popcorn please
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Report this Post05-04-2007 11:40 PM Click Here to See the Profile for cptsnoopySend a Private Message to cptsnoopyDirect Link to This Post
So hard to say. I go with the v-7 because you get the best of both!


ok that was bad... I like the v-8 factor but if I wanted to go fast for least amount of work and money spent it has been proven that the 3800s/c with an auto is the way to go. I doubt that I will ever have a fast v-6 because the wife will cut something off if I start another Fiero project!

[This message has been edited by cptsnoopy (edited 05-04-2007).]

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Report this Post05-05-2007 12:28 AM Click Here to See the Profile for ArchieClick Here to visit Archie's HomePageSend a Private Message to ArchieDirect Link to This Post
 
quote
Originally posted by Dennis LaGrua:

I started this post to take a fair minded look


 
quote
Originally posted by Dennis LaGrua:

an efficent, lightweight, modern, economical V6 engine in your Fiero


 
quote
Originally posted by Dennis LaGrua:

as opposed to using an expensive heavy inefficient gas hungry V8 engine.


Yeah Dennis, you say you want a fair minded look. Then you describe the 2 engine choices in words that show that you plan on being anything but fair minded.

Why don't you tell the truth that you are just looking to get another set of flame wars started like the one's you used to start all the time.

If you want to be fair minded then give a fair minded description of the choices you are wanting to compare.

 
quote
Originally posted by Dennis LaGrua:
In todays times we have cars with 4 and 6 cylinder engines running the 1/4 mile in the 8 and 9 second brackets so it seems that the V6 wins on all counts.


Yes there are 4 and 6 cylinder engines running 8's & 9's in NOPI drags etc. But for every one of them there are 20 V-8 engines outperforming them in the NHRA running in the 6's.

So the V6 is not winning on all counts.

Archie

[This message has been edited by Archie (edited 05-05-2007).]

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Report this Post05-05-2007 12:40 AM Click Here to See the Profile for BlacktreeClick Here to visit Blacktree's HomePageSend a Private Message to BlacktreeDirect Link to This Post
I value handling and braking more than raw power. So a lightweight engine with moderate power output is more to my liking. My idea of the "perfect Fiero engine" would be a V6 with aluminum block and heads, pushrod valvetrain, MPFI, DIS, and a flat torque curve from about 2K-6KRPM.

Does such a thing exist?

[This message has been edited by Blacktree (edited 05-05-2007).]

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Report this Post05-05-2007 12:51 AM Click Here to See the Profile for MstangsBwareSend a Private Message to MstangsBwareDirect Link to This Post
To me it is all about preferance and what you are looking at in a swap. Some want a 1/4 mile car, others want a V-8 for the WOW factor and others just want something that is not the stock duke or 2.8. When I started looking into a swap from the stock 2.8, I first went with the 3.4 but never finished it. Then the 3800SC rolled in and started becoming a popular swap that was a clean install, preformed well and had plenty of aftermarket support. These are some of the key points that drove me to do a 3800SC swap and it couldnt have turned out better. I looked at doing a V-8 swap at one time but really didnt find anything good about the swap for what I wanted it for, which a reliable DD that I can beat on and not have to worry. I told myself I would never do a V-8 being it was jsut not for me but now with LS4 out and avaliable that is attached to the 65E, my mind has changed. We will see once the swap is done how it compares to my MODed 3800SC that is attached to the 65E. I have a strong feeling that the LS4 is going to blow the door off my 3800 car in stock form but time will tell.
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Report this Post05-05-2007 02:10 AM Click Here to See the Profile for PatrickSend a Private Message to PatrickDirect Link to This Post
 
quote
Originally posted by Dennis LaGrua:

I started this post to take a fair minded look at the benefits of using an efficent, lightweight, modern, economical V6 engine in your Fiero as opposed to using an expensive heavy inefficient gas hungry V8 engine.



As fine an example of trolling as I've ever seen here.

[This message has been edited by Patrick (edited 05-05-2007).]

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Report this Post05-05-2007 04:10 AM Click Here to See the Profile for tjm4funSend a Private Message to tjm4funDirect Link to This Post
ahh, what the hell.....
if ya ain;t puttin a bigblock in it, then go with the 6.

Seriously, it depends on what you want. go fast straight line, put the 8 in.
go fast in corners and somewhat in straight line, put a v6 in it.

BTDT with both engines. Right now tho, for a medium to liightweight car that will be a daily driver and a weekend wrrior, I really don;t think you can compare them. if this is a weekend car and a once in a while to work car, th 8 is just the muscle to to put that silly g force pinned to the seat grin on your face.
For economy and a well matched setup tho, I would do the v6. ideally an aluminum one, but that is getting into more money and bleeding edge.
The 3800scII even in stock form will give performance and economy if coupled with the 65eHD, and there is aftermarket support to get right up there in power.
it's all in what you want to use the car for that is the factor. If I could afford 2 I'd have an 8 for the weekends and the 6 for my daily ride. but I can't afford that, so for now it will remain a worked 2.8, and the money will go to the gastank of my boat to feed those 2 chevy 350's that are so grossly overworked. tho with projected 5$/gal on the water, I don;t thinkg they gonna get much work !
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Report this Post05-05-2007 06:52 AM Click Here to See the Profile for HulkSend a Private Message to HulkDirect Link to This Post
 
quote
Originally posted by Dennis LaGrua:

Which is best -V8 or V6? I started this post to take a fair minded look...efficent, lightweight, modern, economical V6 engine...as opposed to using an expensive heavy inefficient gas hungry V8 engine...it seems that the V6 wins on all counts. What's your preference and why?



IMHO, that doesn't even deserve a reply. So what am I doing right now?? Makes about as much sense as your post...

Edit: One of these days, when I have more money than brains, I will put a V10 or V12 into a Fiero, and these type of discussions will be moot. I really don't care for the long rear end it will have though. Kinda like the Lambo or other long engine exotic has...

Personally I'm glad there's such a broad range of preference of powerplants in our cars. It means no matter which one you choose, you will still be unique. If I were concerned with what "the cool kids" or "the in crowd" thought, I wouldn't own a Fiero anyway, I would own some riced out Honda with a stock engine and telling eveyone it runs 10s.

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[This message has been edited by Hulk (edited 05-05-2007).]

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Report this Post05-05-2007 07:59 AM Click Here to See the Profile for OreifClick Here to visit Oreif's HomePageSend a Private Message to OreifDirect Link to This Post
 
quote
Originally posted by Dennis LaGrua:

I started this post to take a fair minded look at the benefits of using an efficent, lightweight, modern, economical V6 engine in your Fiero as opposed to using an expensive heavy inefficient gas hungry V8 engine. In todays times we have cars with 4 and 6 cylinder engines running the 1/4 mile in the 8 and 9 second brackets so it seems that the V6 wins on all counts. What's your preference and why?



First, as usual you have not done your research. A modern V-6 isn't lightweight. The 3800SC is about as heavy as a SBC and heavier than a Northstar or LSx. The 3400 DOHC weighs more than a 3800SC! The 3.9L that GM is pushing now weighs as much as an SBC with aluminum heads and has 100hp less. Engine weight between V-6's and V-8's is not that large of a gap. My car had a 2.8L V-6 with an auto trans. Going to an aluminum headed V-8 with a manual 4-spd I only gained 30 lbs of weight and 210 horsepower. A 3800SC with the 4spd auto trans weighs nearly 65lbs MORE than an iron headed SBC with a manual. Although engine weights have dropped in some cases, The transaxles have increased weight. So if you use a say a 3.6L G6 engine which weighs 5lbs less than the stock 2.8L but hook it up to the 6-spd trans axle which weighs 35 lbs more than the Fiero 5-spd. You have just added 30 lbs of weight to the car for a "lighter" engine.

Second thing is you are assuming a modern V-8 doesn't exsist. The LSx series are modern pushrods and the Northstar is a modern OHC V-8. Both engines have the same efficiency as modern V-6's when compared in terms of horsepower produced. Click the below link and you will see a 3800 vs. a V-8 in terms of gas mileage in the same vehicle is only 1 MPG less than the supercharged engine and only 3 MPG than a normally aspirated V-6. (Also take note that the N/A 3800 gets 2 MPG more than the SC version and the SC has 60hp more power, The V-8 is 43 hp more than the SC version.)
http://www.fueleconomy.gov/...iac_Grand_Prix.shtml

As horsepower goes up gas mileage drops regardless what size engine.
For example a 330hp Cadillac XLR gets 27 mpg with a N/A northstar and 22 mpg with a 462hp supercharged version.

A car that runs the 1/4 mile with a 4 or 6-cylinder in 8 - 9 seconds is NOT going to get 35-40mpg. Fuel consumption is based on flow rate. A 5.7L N/A V-8 flowing 600 CFM is going to use the same amount of fuel as a 2.4L turbocharged 4-cylinder flowing 600cfm. Yes the 4-cyl will be making more horsepower per liter than the V-8 because of forced induction. But the point is both engines are flowing 600cfm of air/fuel. Less boost on the 4-cyl will decrease flow and power and increase gas mileage.

Third as for economical, If you are talking about cost to run, A modified engine (4, 6, or 8 cylinder) is not normally economical. High power modified engines require more maintenance. If you are talking about cost to modify, The SBC and the Ford V-8 are the largest aftermarkets, Then comes the import tuner market. The difference is a cam for the V-8 is less expensive than the Import cams.

Yes in drag racing you have 4 and 6 cylinder cars running 8 - 9 seconds. The V-8's are running 6 - 7 seconds on race gas and 4 seconds with alternative fuels (alchohol and methane).

The biggest problem here is you have already decided you like the V-6 and you are just trolling for a flame war. You really don't care what the facts are and you are even less motivated to actually check them out or see both sides of the discussion.

And finally for the record, There is no "Best Swap".
It is a personal preference by the owner of the car as to which engine they want to swap. If someone wants a DOHC, turbocharged 4-cylinder and another wants a pushrod V-8 with a carb, why should we care. It's not as if they did it "right or wrong" but they did it the way that they wanted. Now there are some people who do foolish things like putting a restrictive intake on a turbocharged engine, For these folks we can only offer technical advice on how to make their engine perform better and hope that they want to actually learn.

[This message has been edited by Oreif (edited 05-05-2007).]

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Report this Post05-05-2007 08:14 AM Click Here to See the Profile for Joseph UpsonSend a Private Message to Joseph UpsonDirect Link to This Post
 
quote
Originally posted by Dennis LaGrua:
I started this post to take a fair minded look at the benefits of using an efficent, lightweight, modern, economical V6 engine in your Fiero as opposed to using an expensive heavy inefficient gas hungry V8 engine. In todays times we have cars with 4 and 6 cylinder engines running the 1/4 mile in the 8 and 9 second brackets so it seems that the V6 wins on all counts. What's your preference and why?


That's an uncomplicated straight forward question, no sarcasm or insults warranted, just a constructive oppinion.

There has always been a replacement for displacement. Since I along with many others have spewed out conclusions without any scientific data available to support on many occasions and ultimately have wound up being wrong, I try to stick with documented numbers and formulas more.

Theoretically if you spin an engine half the size of a larger engine at twice the rpm of the larger engine you get the same horsepower output as long as the efficiency compliments it at the higher rpm, you can then recover a large amount of the torque with appropriate gearing in the transmission. What Dennis is doing is recognizing the fact that the V6 engines are now producing stock unboosted horsepower levels that a few short years ago many of us were wanting to switch to a V8 to get.

The V8 has a peformance history, aftermarket support and character, not much can easily be compared to the exhaust note or torque, but I'll inject my own fair mindedness and say having owned one in a Fiero, for the iron block it is heavy and although I appreciated the sound and the power, I didn't like the feel of the added wt or the solid mount and I drive my car in a manner that was affected by the unbalance, it also takes up a lot of space.

I sided with the V6 because it has a nice Formula 1 class exhaust note (you should hear the new Nissans on the pedal) they are much more powerful and fuel efficient than they use to be, 3.6 DOHC 275hp/258lb-ft, 3900HO 270hp/258lb-ft, 3500 200hp/220lb/ft all have 6000 or higher rpm cut offs, steel cranks, forged rods, piston cooling oil squirters and 4-bolt mains with the help of the aluminum oil pan. The 3.6 is a stretch for the moment until the electronics is worked out but it will not be long. They are all in GM trim which means there's plenty more power in them, the 3900HO is proof of that being up by 30hp over the initial base engine. The 3.6 is aluminum, block and heads, and the others probably equal to the 2.8L if not lighter. When I started turbocharging everything and drove a V8 Fiero for a little while I favored the V6 which I like the sound of mixed with the turbine.

The numbers don't lie, I want good fuel economy, light weight and lots of power, it takes a turbo to get the power level I want but I'm still well within weight limits and if my current turbo 3100 is any proof I still win on gas mileage to with conservative pedal application, and that is actually the hard part.

To each his own

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Report this Post05-05-2007 08:35 AM Click Here to See the Profile for Joseph UpsonSend a Private Message to Joseph UpsonDirect Link to This Post

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quote
Originally posted by Oreif:
The 3.9L that GM is pushing now weighs as much as an SBC with aluminum heads and has 100hp less.


Where did you get this information, I just disassembled a 3900 and compared to my previous experience with other V6 engines and the SBC, I didn't feel that kind of weight difference in the block. The steel crank is a second design of which I have one of both and I believe the 3900 steel crank is lighter than the first design in my 3500 because it was trimmed and they account for about a 10-15lb increase between them. The intake design adds very little additional weight and the aluminum heads are about 15lbs each lighter than the cast iron V6 heads. As for 100hp less I'd say that's not bad being short 2 cylinders, 3900HO 270hp/6= 45hp/cyl * 8cyl = 360 hp if it had 8 cyl at its current power potential per cylinder.

They've lightened the newer V8 engines which I believe is not reasonable to call a small block chevy because it fails to differentiate between the LS series that it is and the true SBC that most I believe are still swopping as the V8 of choice, two entirely different engines.


Govt fuel economy estimates are just that, and lately have been under scrutiny because of considerable discrepancy from actual.

[This message has been edited by Joseph Upson (edited 05-05-2007).]

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Report this Post05-05-2007 09:06 AM Click Here to See the Profile for project34Send a Private Message to project34Direct Link to This Post
I've a V-6, not a V-8, but I think V-8 Archie's earlier comments in this thread about Dennis LaGrua's so-called "fair-minded" comparison are well taken.

With all due respect, his use of the term, "fair-minded" in initiating the present thread in my opinion strains his credibility because of the very way he's phrased things in his original post:

 
quote
Originally posted by Dennis LaGrua:

I started this post to take a fair minded look at the benefits of using an efficent, lightweight, modern, economical V6 engine in your Fiero as opposed to using an expensive heavy inefficient gas hungry V8 engine.


Dennis's post, however, did give me quite the chuckle in that it reminded me of local politicians in my area who say things like, "Unlike my opponent, I will NOT stoop to name-calling with regard to my opponent's immoral behavior..."

Nevertheless, I'd really like to someday learn from Dennis more about his work with turbocharging the pushrod 3.4L, even though, as he's stated on other threads, he now favors another V-6 engine. (However, I also recognize that this is a separate topic from the "fair-minded" one Dennis posted here.)
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Report this Post05-05-2007 09:12 AM Click Here to See the Profile for ryan.hessSend a Private Message to ryan.hessDirect Link to This Post
 
quote
Originally posted by Oreif:The 3400 DOHC weighs more than a 3800SC!


Or the northstar. I think it gets equivalent gas mileage too (~24mpg hwy)

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Report this Post05-05-2007 10:14 AM Click Here to See the Profile for Joseph UpsonSend a Private Message to Joseph UpsonDirect Link to This Post
 
quote
Originally posted by project34:

I've a V-6, not a V-8, but I think V-8 Archie's earlier comments in this thread about Dennis LaGrua's so-called "fair-minded" comparison are well taken.

With all due respect, his use of the term, "fair-minded" in initiating the present thread in my opinion strains his credibility because of the very way he's phrased things in his original post:


Dennis's post, however, did give me quite the chuckle in that it reminded me of local politicians in my area who say things like, "Unlike my opponent, I will NOT stoop to name-calling with regard to my opponent's immoral behavior..."

Nevertheless, I'd really like to someday learn from Dennis more about his work with turbocharging the pushrod 3.4L, even though, as he's stated on other threads, he now favors another V-6 engine. (However, I also recognize that this is a separate topic from the "fair-minded" one Dennis posted here.)


It's better to give the benefit of the doubt for peace sake in these situations, I've offended people unintentionally by my choice of words and phrases, not so much by what I stated directly, but by how it was interpreted by the individual reading it. I believe the same thing has happened here, his "fair minded" statement might have been an indirect way of saying just state your choice and why without any bickering or allegations of being a trouble starter. Even if he had been more direct I doubt it would have made any difference, it's unfortunately difficult to ask a question on this forum of that nature without the likelyhood of some heated interpretation. The best thing to do when it occurs is not feed it by responding in a manner that fuels it along, which so far he has done a good job of abstaining from.

If everyone would focus on the actual question and resist the urge to interpret, a lot of good info can be imparted in providing the new members who are proned to asking this kind of question the info they need to make the decision.

 
quote
Originally posted by Dennis LaGrua:
What's your preference and why?


Just focus on that and this can be a very productive and informative thread.

[This message has been edited by Joseph Upson (edited 05-05-2007).]

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Report this Post05-05-2007 10:27 AM Click Here to See the Profile for OreifClick Here to visit Oreif's HomePageSend a Private Message to OreifDirect Link to This Post
 
quote
Originally posted by Joseph Upson:


Where did you get this information, I just disassembled a 3900 and compared to my previous experience with other V6 engines and the SBC, I didn't feel that kind of weight difference in the block. The steel crank is a second design of which I have one of both and I believe the 3900 steel crank is lighter than the first design in my 3500 because it was trimmed and they account for about a 10-15lb increase between them. The intake design adds very little additional weight and the aluminum heads are about 15lbs each lighter than the cast iron V6 heads. As for 100hp less I'd say that's not bad being short 2 cylinders, 3900HO 270hp/6= 45hp/cyl * 8cyl = 360 hp if it had 8 cyl at its current power potential per cylinder.

They've lightened the newer V8 engines which I believe is not reasonable to call a small block chevy because it fails to differentiate between the LS series that it is and the true SBC that most I believe are still swopping as the V8 of choice, two entirely different engines.


Govt fuel economy estimates are just that, and lately have been under scrutiny because of considerable discrepancy from actual.



Shipping weight of a 3900 is 404 lbs
Shipping weight of a ZZ4 is 405 lbs
Only difference between the two is the ZZ4 comes without carb and the 3900 has the entire intake and TB on it.
The stock 3900 is only 240 hp per Pontiac's website.
So 240/6 = 40 40* 8 = 320 hp So thanks for proving that a modern V-6 and a modern V-8 have nearly the same efficiency contrary to what the original author of this thread says.

3900 = 61.5 hp per liter
LS2 = 66.6 hp per liter
ZZ4 with a carb = 62.2 hp per liter

Now these are normally aspirated, I'm sure Dennis will bring up boosted engines so:
Cobalt SS 2.2L SC = 93 hp per liter
XLR Northstar SC = 98 hp per liter


I know that there are some engines with greater efficiency, All Honda engines are normally aspirated and very efficient, but since this is a Fiero Forum I suspect the engines that are normally swapped into a Fiero are the ones being compared. If you are talking about any engine in production, The Honda S2000 hits 100hp per liter normally aspirated as an example of high efficiency. Top fuel dragsters hit 675hp per liter using boost and alternative fuel. So there are others, we can come up with numerous examples all day long, but with respect to Fiero swaps it isn't practical.

[This message has been edited by Oreif (edited 05-05-2007).]

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Report this Post05-05-2007 10:35 AM Click Here to See the Profile for vortecfieroClick Here to visit vortecfiero's HomePageSend a Private Message to vortecfieroDirect Link to This Post
when the decision time came for me.. i looked to what i would need in the future as well as now,
did the research, made a decision and stuck with it. Im happy with my decision.
V8 guys could go through the same process and decided on a V8 and still happy with their decision
as well.

------------------



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S10 caliper conversion.
Murphy's Constant Matter will be damaged in direct proportion to its value
Murphy's Law of Thermodynamics Things get worse under pressure.
Arthur C. Clarke "Any significantly advanced technology is indistinguishable from magic"

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Report this Post05-05-2007 10:39 AM Click Here to See the Profile for Joseph UpsonSend a Private Message to Joseph UpsonDirect Link to This Post
 
quote
Originally posted by Oreif:


Shipping weight of a 3900 is 404 lbs
Shipping weight of a ZZ4 is 405 lbs
Only difference between the two is the ZZ4 comes without carb and the 3900 has the entire intake and TB on it.
The stock 3900 is only 240 hp per Pontiac's website.
So 240/6 = 40 40* 8 = 320 hp So thanks for proving that a modern V-6 and a modern V-8 have nearly the same efficiency contrary to what the original author of this thread says.

3900 = 61.5 hp per liter
LS2 = 66.6 hp per liter
ZZ4 with a carb = 62.2 hp per liter

Now these are normally aspirated, I'm sure Dennis will bring up boosted engines so:
Cobalt SS 2.2L SC = 93 hp per liter
XLR Northstar SC = 98 hp per liter


I know that there are some engines with greater efficiency, All Honda engines are normally aspirated and very efficient, but since this is a Fiero Forum I suspect the engines that are normally swapped into a Fiero are the ones being compared. If you are talking about any engine in production, The Honda S2000 hits 100hp per liter normally aspirated as an example of high efficiency. Top fuel dragsters hit 675hp per liter using boost and alternative fuel. So there are others, we can come up with numerous examples all day long, but with respect to Fiero swaps it isn't practical.



I need to see pictures of both engines on a crate prepared for shipping because it defies logic just by comparison of both cast iron blocks, aluminum heads and crankshafts alone, it just doesn't add up because those three items alone have more than a 4 inch difference in length between them.

The 270HP 3900HO is an upgrade from the 242 HP version, and I'm about to purchase the 07 Shop manual to get a better understanding of how it all works (VVT particularly for the 3.6) and the tiptronic transmission. I have purchased a hobbyist Stamp Works kit to start learning some programming and interfacing of sensor control so that I can put it to use in this area.
I mentioned in another thread my Mom bought a Saturn Aura with the 3.6 DOHC and 6spd Semi automatic and except for the delayed electronic shift it's nothing to laugh at in acceleration. Depending on the application the 3.6 has a fuel shut off of 7000 rpm, there's no red area on her rpm gauge which I think goes up to about 8-9K.


Oh yeah, the 3900 cylinder heads were designed after the LS1 heads but GM went back and did a little more work on them and the cam to help push the engine to 270HP, and were it not for the wide LSA (~118 deg) of the camshaft which helped eliminate the EGR from my DYNO simulations it would be even higher than that.

[This message has been edited by Joseph Upson (edited 05-05-2007).]

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Report this Post05-05-2007 10:47 AM Click Here to See the Profile for trotsSend a Private Message to trotsDirect Link to This Post
i doubt the handling is affected much with a v8. so i think thats stupid to say well i like good handling so i dont want a v8.
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Report this Post05-05-2007 10:51 AM Click Here to See the Profile for Joseph UpsonSend a Private Message to Joseph UpsonDirect Link to This Post
 
quote
Originally posted by trots:

i doubt the handling is affected much with a v8. so i think thats stupid to say well i like good handling so i dont want a v8.


I wish you could have taken a ride in my V8 Fiero, or better yet taken a curb at the speeds I do with the V6. If it's an iron V8 you will know that it's back there and not just because you can hear it.
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Report this Post05-05-2007 02:30 PM Click Here to See the Profile for project34Send a Private Message to project34Direct Link to This Post
 
quote
Originally posted by Joseph Upson:

his "fair minded" statement might have been an indirect way of saying just state your choice and why

So based on the comment above, if Dennis LaGrua (whom I've said in an earlier post on this thread is someone I'd like to learn from in regard to his 3.4L turbocharging efforts) says one thing, I should interpret it to be some OTHER thing? Maybe the other members of PFF have it figured out as to how that works, but unfortunately for me, my own telepathic skills are sorely wanting.

[This message has been edited by project34 (edited 05-05-2007).]

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Report this Post05-05-2007 03:08 PM Click Here to See the Profile for Joseph UpsonSend a Private Message to Joseph UpsonDirect Link to This Post
 
quote
Originally posted by project34:

So based on the comment above, if Dennis LaGrua (whom I've said in an earlier post on this thread is someone I'd like to learn from in regard to his 3.4L turbocharging efforts) says one thing, I should interpret it to be some OTHER thing? Maybe the other members of PFF have it figured out as to how that works, but unfortunately for me, my own telepathic skills are sorely wanting.



Perfect example of what I was trying to convey, if I understand you correctly it appears you took my statement to mean something negative regarding what he said, you can interpret what he said however you like, I just don't see where he has said anything that warrants temper flares. I intended to suggest that he was probably aware of the controversy such a thread like this might generate and added a qualifier "fair minded" in hopes of diffusing it before hand and it seems it did just the opposite. It's possible he meant to cause a fuss but unless he admits to it I will not assume so. He has one of the best minds to "pick" for the subject of turbocharging, I can't justify saying otherwise. Most of us have a strong following behind our personal preferences and it shows doesn't it.

As I stated earlier, perhaps focusing on the actual question " What's your preference and why? " will keep things nice and constructive.
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Report this Post05-05-2007 03:55 PM Click Here to See the Profile for jscott1Send a Private Message to jscott1Direct Link to This Post
 
quote
Originally posted by Dennis LaGrua:

the benefits of using an efficent, lightweight, modern, economical V6 engine in your Fiero as opposed to using an expensive heavy inefficient gas hungry V8 engine.




So when did you stop beating your wife?...some questions don't deserve an answer.
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Report this Post05-05-2007 04:00 PM Click Here to See the Profile for WAWUZATSend a Private Message to WAWUZATDirect Link to This Post
I'll stick with my 6.8L V10 ... in the '05 Excursion.
4.6L V8 Northstar going in the '85 Fiero (GT40 rebody).
Will leave the 4.0L V6 in my wife's '05 'Stang ... but I did add dual exhaust with an H-pipe to it.
And the V2 in the Harley gets the best MPG ... about 45 around town.
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Report this Post05-05-2007 04:16 PM Click Here to See the Profile for project34Send a Private Message to project34Direct Link to This Post
 
quote
Originally posted by Dennis LaGrua:

I started this post to take a fair minded look at the benefits of using an efficent, lightweight, modern, economical V6 engine in your Fiero as opposed to using an expensive heavy inefficient gas hungry V8 engine. In todays times we have cars with 4 and 6 cylinder engines running the 1/4 mile in the 8 and 9 second brackets so it seems that the V6 wins on all counts. What's your preference and why?


Suppose we took out the words, "fair minded" from Dennis's comment.

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Report this Post05-05-2007 05:19 PM Click Here to See the Profile for OreifClick Here to visit Oreif's HomePageSend a Private Message to OreifDirect Link to This Post
 
quote
Originally posted by Joseph Upson:


I wish you could have taken a ride in my V8 Fiero, or better yet taken a curb at the speeds I do with the V6. If it's an iron V8 you will know that it's back there and not just because you can hear it.


Curb? I think you mean curve.

Anyhow, I went from an auto V-6 to a manual V-8 and I have not noticed any handling differences except how much gas you give it when racing around a road course. The suspension was modified with lowering springs, poly bushings and KYB strut/shocks, It should be noted that the suspension was the exact same with both drivetrains. Actual MPH in the corners is the same, I just can't floor the V-8 when exiting the corner like I could do with the V-6. The rear will break loose with more gas but that is a factor of the engines power not the additional 30 lbs.
I could see adding a V-8 to a worn stock suspension would make for some possible handling issues because of weight or increased torque, But I would bet if the suspension was new (stock) it would not have as many issues.

One question I would like to ask is do the folks with the 3800SC's have handling issues? Everyone always says the V-8's ruin the handling due to weight, But a 3800SC with a 4-spd auto is heavier. I don't recall seeing anyone complaining about handling being affected in a 3800Sc swap. I would suspect if weight was the issue, The 3800Sc, SBC, 3.4L DOHC, and Northstar swaps would all affect handling.
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Report this Post05-05-2007 06:29 PM Click Here to See the Profile for trotsSend a Private Message to trotsDirect Link to This Post
 
quote
Originally posted by Oreif:
Anyhow, I went from an auto V-6 to a manual V-8 and I have not noticed any handling differences except how much gas you give it when racing around a road course. The suspension was modified with lowering springs, poly bushings and KYB strut/shocks, It should be noted that the suspension was the exact same with both drivetrains. Actual MPH in the corners is the same, I just can't floor the V-8 when exiting the corner like I could do with the V-6. The rear will break loose with more gas but that is a factor of the engines power not the additional 30 lbs.
I could see adding a V-8 to a worn stock suspension would make for some possible handling issues because of weight or increased torque, But I would bet if the suspension was new (stock) it would not have as many issues.

One question I would like to ask is do the folks with the 3800SC's have handling issues? Everyone always says the V-8's ruin the handling due to weight, But a 3800SC with a 4-spd auto is heavier. I don't recall seeing anyone complaining about handling being affected in a 3800Sc swap. I would suspect if weight was the issue, The 3800Sc, SBC, 3.4L DOHC, and Northstar swaps would all affect handling.


very informative, thanks.

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Report this Post05-05-2007 09:05 PM Click Here to See the Profile for wftbSend a Private Message to wftbDirect Link to This Post
the overwhelming engine of choice ,back when there was a choice ,was the inline 4 cylinder motor .four cylinder motors have almost twice the wins of any other configuration at the indy 500.i will not build a v8 powered anything .
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Report this Post05-06-2007 07:22 AM Click Here to See the Profile for OreifClick Here to visit Oreif's HomePageSend a Private Message to OreifDirect Link to This Post
Dennis??
(Chirp, Chirp, Chirp,)

Huh, Guess it didn't turn into the "flame war" he had hoped for.
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Report this Post05-06-2007 09:32 AM Click Here to See the Profile for WillSend a Private Message to WillDirect Link to This Post
 
quote
Originally posted by Dennis LaGrua:

fair minded look

efficent, lightweight, modern, economical V6 engine
expensive heavy inefficient gas hungry V8 engine.



Yeah, this is fair minded. As fair minded as it gets.

Don't forget, Dennis, that the automatic transmissions of which you are constantly singing praises are between 150 and 200 pounds heavier than the stickshift transmissions available for the Fiero. For a naturally aspirated car, the difference in weight makes up for the difference in shifting times. I've actually run faster 1/4 mile times in my stickshift Northstar car than Ryan has in his MANUALLY SHIFTED automatic Northstar car.

Now a turbo car definitely benefits from using an automatic, but the difference between auto and stick with turbo cars is getting smaller thanks for modern turbo technology like fast spooling low inertia wheels and ball bearing center sections.

[This message has been edited by Will (edited 05-06-2007).]

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Report this Post05-06-2007 09:36 AM Click Here to See the Profile for project34Send a Private Message to project34Direct Link to This Post
 
quote
Originally posted by Oreif:

A modern V-6 isn't lightweight. The 3800SC is about as heavy as a SBC and heavier than a Northstar or LSx. The 3400 DOHC weighs more than a 3800SC!


I like this forum because I'm almost always learning something from it, often even when I don't expect to. Now if only I could REMEMBER that a modern V-6 isn't particularly lightweight relative to a V-8, and that the 3400DOHC in particular isn't lightweight!
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Report this Post05-06-2007 09:46 AM Click Here to See the Profile for WillSend a Private Message to WillDirect Link to This Post
Weight really depends on construction.

Northstar and LSx have about the same level of technology in their designs, but the LSx is lighter and more compact engine precisely because of its "primitive" pushrod valvetrain.

An all aluminum pushrod V6 would be the lightest 6 or 8, but I'd hazard a guess that the new global V6's with DOHC cylinder heads are probably in the same weight range as an LSx.

It's too bad that GM doesn't understand V6's or they would have pushed the pushrod 6 concept as far as they've pushed the pushrod 8 concept and we'd have some REALLY light V6's available for the Fiero.

The king of light weight remains the Ecotec, however.

So, Dennis, why would anyone want a heavy gas guzzling 6 cylinder when they can have a lightweight, efficient 4 cylinder that's been proven in competition at 4 digit power levels?
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Report this Post05-06-2007 09:54 AM Click Here to See the Profile for RaydarSend a Private Message to RaydarDirect Link to This Post
 
quote
Originally posted by FieroMonkey:
can someone pass me some popcorn please


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Report this Post05-06-2007 10:02 AM Click Here to See the Profile for ryan.hessSend a Private Message to ryan.hessDirect Link to This Post
 
quote
Originally posted by Will:
I've actually run faster 1/4 mile times in my stickshift Northstar car than Ryan has in his MANUALLY SHIFTED automatic Northstar car.

Well, to be fair, that was my first and (so far) only time at a track. And I shifted early 1-2. But I don't think I could match your times with a perfect run either....

 
quote
Originally posted by Will:
So, Dennis, why would anyone want a heavy gas guzzling 6 cylinder when they can have a lightweight, efficient 4 cylinder that's been proven in competition at 4 digit power levels?


4 banger for the win!!
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Report this Post05-06-2007 10:23 AM Click Here to See the Profile for BlacktreeClick Here to visit Blacktree's HomePageSend a Private Message to BlacktreeDirect Link to This Post
 
quote
Will said: It's too bad that GM doesn't understand V6's or they would have pushed the pushrod 6 concept as far as they've pushed the pushrod 8 concept and we'd have some REALLY light V6's available for the Fiero.

My thoughts exactly. An all-aluminum 3800 would make me a very happy man.
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Report this Post05-06-2007 10:49 AM Click Here to See the Profile for Joseph UpsonSend a Private Message to Joseph UpsonDirect Link to This Post
 
quote
Originally posted by Oreif:
Curb? I think you mean curve. .


I don't suppose you noticed that "B" is right next to "V" on the keyboard and that was a typo, I've spent a lot of time trying to break the habit of feeling I need to be grammatically perfect on the forum so I could post quicker now you've messed "me" head up and I've reverted back to that obsessive compulsive behavior.

My V8 swop was on a stock suspension so I doubt you would experience the kind of handling effects that I did, especially with poly parts and a lower center of gravity, those two improvements alone would greatly improve handling.

Regarding the weight comparison of the 3900 vs. a ZZ4 crate motor posted earlier, where the 3900 shipping weight came out to be a little more than the ZZ4, someone explained regarding some weights he was familiar with that an all aluminum LSx motor fully dressed weighs about 400 lbs which is about what the all iron 60 degree engine weighs fully dressed. The V6 aluminum heads are about 15lbs each lighter than the cast iron heads so as I suspected as a result of the cast iron V8 block those shipping weights can't be right and it's either a typo or a base rate across the board for catagory or more parts are included with the V6.

Here is a Dyno simulation of a 350 TPI with a high performance cam and headers, against the 3900 with increased duration and a little shortening of the stock LSA from 118 to 115 on 7psi and 15 degrees of retard which the VVT is capable of at a minimum. The VVT cam characteristics allow it to increase performance at such a high degree of retard because when the cam in the 350 is retarded beyond about 3 degrees power starts to drop considerably, note the flat character of the torque curve for the V6 (diamond studded curves).
Obviously the V6 is no match for the V8 at 7 psi off the line and up to about 5500 rpm but after that all shifts will be at that point or higher so off line to 5500 is the V8s only advantage after which it will suffer from characteristic American Muscle syndrome, no air up top and that's why "them" smaller imports have been able to give the larger engines a hard time on the open road. If you have 400 lb-ft and can only stick 300 of it to the ground vs a smaller engine with 300 lb-ft max and can stick all of it to the ground the advantage is lost unless you can win the horsepower war which usually favors the smaller engines.

Of course you can get more naturally aspirated power than that from the V8 but that is about the range a lot of the swops are operating in if not for the most part lower. This comparison is for my purposes in making the decision I have made so I'm not saying the V6 is the better engine. It's best for what I want to do: get high MPG when driven civilized and high output when driven to the contrary. With the V8 there is more limitation to fuel economy simply because you have to feed the amount of air it pulls in with the appropriate amount of fuel, so as mentioned earlier by another member, increased horsepower does not necessarily decrease fuel economy because you can increase power by simply making the engine more efficient, if you increase displacement you are pulling in more air and fuel increase to maintain proper airfuel ratio is mandatory so although it can also be offset with increased efficiency, it is more likely to decrease MPG. Chevy V8s are still for the most part stuck in the sub 30 MPG range though I'm sure someone is above that, the later V6 options particularly the 3800 swops placing well above the 30 MPG range from what I have read.

I really like the sound of the 6 banger and turbo at the rpm ceiling, it compliments the car better in my opinion.



I have the stronger LS6 springs for my engine and it will see all of 7000 rpm and 10 psi boost which will push it well above 400 hp, whether it can take it or not, it's time to stop speculating and prove. I would rather risk blowing up an engine from piston failure since everything else is forged and then turn the boost down on the replacement engine since the cost of the replacement is not significantly more than Forged pistons which so far I have received a best quote of $530 on. I have located 3900s within driving distance of home for as low as $650 and I believe the engine to be very capable of 400/400 from what the stock weaker 3400s are surviving under.

[This message has been edited by Joseph Upson (edited 05-06-2007).]

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Report this Post05-06-2007 11:46 AM Click Here to See the Profile for OreifClick Here to visit Oreif's HomePageSend a Private Message to OreifDirect Link to This Post
 
quote
Originally posted by Joseph Upson:
I don't suppose you noticed that "B" is right next to "V" on the keyboard and that was a typo, I've spent a lot of time trying to break the habit of feeling I need to be grammatically perfect on the forum so I could post quicker now you've messed "me" head up and I've reverted back to that obsessive compulsive behavior.



I meant it in humor with the curb/curve thing. Hence the "wink".
Sorry if it came off as anything else.

 
quote
Originally posted by Joseph Upson:
My V8 swop was on a stock suspension so I doubt you would experience the kind of handling effects that I did, especially with poly parts and a lower center of gravity, those two improvements alone would greatly improve handling.


True, but in comparison between the two drivetrains there was no difference. If weight was as large of a factor as some make it out to be, Then as I noted above many other swaps would have the same issues, But so far I have not heard of anyone complaining about adverse effects of handling with other heavier swaps. Like I stated a 3800SC with the 4-spd auto is a really heavy swap and does have the power of a V-8. Adding some weight forward of the rear axle should not make much difference in a mid-engine designed chassis. The only thing I can think of would be suspension flex with the increased torque due to worn out suspension components.

 
quote
Originally posted by Joseph Upson:
Regarding the weight comparison of the 3900 vs. a ZZ4 crate motor posted earlier, where the 3900 shipping weight came out to be a little more than the ZZ4, someone explained regarding some weights he was familiar with that an all aluminum LSx motor fully dressed weighs about 400 lbs which is about what the all iron 60 degree engine weighs fully dressed. The V6 aluminum heads are about 15lbs each lighter than the cast iron heads so as I suspected as a result of the cast iron V8 block those shipping weights can't be right and it's either a typo or a base rate across the board for catagory or more parts are included with the V6.


Shipping weight of my ZZ4 was the actual weight on the crate. I assume that the shipping company did not guess or typo the item they were shipping.

 
quote
Originally posted by Joseph Upson:
Here is a Dyno simulation of a 350 TPI with a high performance cam and headers, against the 3900 with increased duration and a little shortening of the stock LSA from 118 to 115 on 7psi and 15 degrees of retard which the VVT is capable of at a minimum. The VVT cam characteristics allow it to increase performance at such a high degree of retard because when the cam in the 350 is retarded beyond about 3 degrees power starts to drop considerably, note the flat character of the torque curve for the V6 (diamond studded curves).
Obviously the V6 is no match for the V8 at 7 psi off the line and up to about 5500 rpm but after that all shifts will be at that point or higher so off line to 5500 is the V8s only advantage after which it will suffer from characteristic American Muscle syndrome, no air up top and that's why "them" smaller imports have been able to give the larger engines a hard time on the open road. If you have 400 lb-ft and can only stick 300 of it to the ground vs a smaller engine with 300 lb-ft max and can stick all of it to the ground the advantage is lost unless you can win the horsepower war which usually favors the smaller engines.

Of course you can get more naturally aspirated power than that from the V8 but that is about the range a lot of the swops are operating in if not for the most part lower. This comparison is for my purposes in making the decision I have made so I'm not saying the V6 is the better engine. It's best for what I want to do: get high MPG when driven civilized and high output when driven to the contrary. With the V8 there is more limitation to fuel economy simply because you have to feed the amount of air it pulls in with the appropriate amount of fuel, so as mentioned earlier by another member, increased horsepower does not necessarily decrease fuel economy because you can increase power by simply making the engine more efficient, if you increase displacement you are pulling in more air and fuel increase to maintain proper airfuel ratio is mandatory so although it can also be offset with increased efficiency, it is more likely to decrease MPG. Chevy V8s are still for the most part stuck in the sub 30 MPG range though I'm sure someone is above that, the later V6 options particularly the 3800 swops placing well above the 30 MPG range from what I have read.



The 3900 is a pushrod engine isn't it? The dyno chart is great for bench top dyno, But do you really think a 3900 pushrod will get over 7000 RPM?? It will run out of RPM's due to valve train limitations before it hits 7500rpm peak power. Another example is the Honda S2000, It screams upwards of 8000 rpm but anything below 5000 it is a dog. Yes it has 240hp but you need to wind up the engine before you get into the power band. If you were doing rolling races the high RPM/power engines would have the advantage but an engine like the SBC with the lower power band and torque would do better off the line from a stop. Even a stock V-6 Fiero can jump ahead of the S2000 off the line. (Of course by 30ft the S2000 is in it's power band and screams past you) Again this all falls back onto what the owner prefers. Do you want to wind up into the 7000 to 8000 rpm range or a "push you into the seat off the line" style of car? Do you want it to act like a high end sports car or more like a streetrod/muscle car? The choice is the owners to make.

As for gas mileage, Why does everyone always bring this up when talking about wanting high performance? When I did my swap, gas mileage wasn't even a consideration. Yes a 3800SC in a Fiero gets into the 30mpg range, but I personally am not trying to get the best mileage in my particular set up. Someone who drives their car daily this could be a factor, but strictly from a power standpoint it really isn't a consideration.
Again it all comes down to what the owner wants.


 
quote
Originally posted by Joseph Upson:
I really like the sound of the 6 banger and turbo at the rpm ceiling, it compliments the car better in my opinion.


That is how you want your car to act/feel. There is nothing wrong with that, I just feel that some of the other folks around here tend to push their own personal choice onto others or criticize them when discussing swaps and that I feel is not right. The person who is trying to figure out what swap to do should check out each swap and decide for themselves what they want and how they want the car to feel, handle, and perform.

As an example look at the original post in theis thread, You can already see the author does not favor a V-8 swap. It's hard to be "fair-minded" when you start off by already having a bad opinion of a particular swap.

[This message has been edited by Oreif (edited 05-06-2007).]

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Report this Post05-06-2007 12:03 PM Click Here to See the Profile for Joseph UpsonSend a Private Message to Joseph UpsonDirect Link to This Post
 
quote
Originally posted by Oreif:


The 3900 is a pushrod engine isn't it? The dyno chart is great for bench top dyno, But do you really think a 3900 pushrod will get over 7000 RPM?? It will run out of RPM's due to valve train limitations before it hits 7500rpm peak power. Another example is the Honda S2000, It screams upwards of 8000 rpm but anything below 5000 it is a dog. Yes it has 240hp but you need to wind up the engine before you get into the power band. If you were doing rolling races the high RPM/power engines would have the advantage but an engine like the SBC with the lower power band and torque would do better off the line from a stop. Even a stock V-6 Fiero can jump ahead of the S2000 off the line. (Of course by 30ft the S2000 is in it's power band and screams past you) Again this all falls back onto what the owner prefers. Do you want to wind up into the 7000 to 8000 rpm range or a "push you into the seat off the line" style of car? Do you want it to act like a high end sports car or more like a streetrod/muscle car? The choice is the owners to make.

As for gas mileage, Why does everyone always bring this up when talking about wanting high performance? When I did my swap, gas mileage wasn't even a consideration. Yes a 3800SC in a Fiero gets into the 30mpg range, but I personally am not trying to get the best mileage in my particular set up. Someone who drives their car daily this could be a factor, but strictly from a power standpoint it really isn't a consideration.
Again it all comes down to what the owner wants.



I didn't take what you said personally at all and understood you meant no harm.

You forget that the 3900 has variable valve timing, and a variable length intake runner and both the base and HO engines make their horsepower peak at the 6000 rpm mark on the Dyno curves GM listed, also the cylinder head ports are larger than those found on the previous V6 engines as well as the valves 1.87 intake and 1.52 exhaust. My cam will have more duration and lift in addition to the turbos and both add rpm to the base margin which is already 6K and I mentioned that I have LS6 beehive springs which are a lot stronger than the stock 3.9L springs. The VVT module retards the cam with rpm increase to help maintain efficiency over the rpm range as well as give you a higher rpm peak so you get the best of both worlds, good bottom end performance and good top end performance. I'm only going for the 7K mark.

Gas mileage is important for me because I'm still a student and for the past 3 and a half months have been driving an average of more than 90 miles a day 4 to 5 days a week, at what's now about $3 gal, I can't ignore mileage at this point in my education. The gas pumps are not setup yet to accept knowledge as a form of payment.

The base reading for Dyno on the 3900 was about 25 hp lower than actual when I put the specs in but part of that is due to 3500 V6 head flow numbers and a slightly shorter than stock duration exh timing due to the program limitations for the actual cam specs it has, otherwise it has been pretty close to documented specs except erroring on the low side of actual HP.

[This message has been edited by Joseph Upson (edited 05-06-2007).]

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Dennis LaGrua
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Report this Post05-06-2007 12:27 PM Click Here to See the Profile for Dennis LaGruaSend a Private Message to Dennis LaGruaDirect Link to This Post
 
quote
Originally posted by Oreif:

Dennis??
(Chirp, Chirp, Chirp,)

Huh, Guess it didn't turn into the "flame war" he had hoped for.


It's funny that when you start a post that just poses a question; it is sometimes interpreted as trying to start a flame war. The purpose of any forum is simply for the open exchange of ideas and opinions. Asking for an opinion or a statement on ones preference cannot be construed as flaming.
As for my preference; after seeing what Zoomer over at ZZ Performance has done with the 3800SC platform , I was sold on the fact that this engine provides what I am looking for- a reasonably inexpensive swap that can provide performance, technology, strength and economy. It's also an easy fit in the engine compartment, low mileage engines are abundant, performance parts are available, it's an easy engine to modify, it looks good and requires no special conversion kit. FYI, Zoomer runs the 1/4 mile in the 9's ( documented) with a 3800SC in a much heavier Grand Prix. The potential is there to build one fast Fiero with this engine and it may be becoming the most popular Fiero swap. The 3800SC may not be for everyone but this V6 is best for my application so thats how I answer the question.

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87GT 3.4 Turbo- 0-60 5.2 seconds -Best
Engine Controls, ECM goodies, Chip
re-programming & odd electronics stuff

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