My '95 DOHC was an interference motor.

Try to get a ride in one of each. then ask yourself how much of the swap your going to do. Ask a few questions about the difficulty of each swap. Get a good idea of the money you think it will cost, then double it. Figure out how much time you think you will devote to it, and triple it. Then just do it. Don't let anyone tell you what to do.

BUT, If I was doing it all over again. I would go with an LS3 and 6 speed. Both the DOHC and 4.9 are old school and have ZERO support.

Rob.

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

88 TTop coupe (96 3.4DOHC/5 speed "almost done)"
03 Vibe GT. 6spd (stock)
05 GTO, LS2, 6spd (not stock)
84 SE "Vert" (oh boy, what did I do now)

I always liked the way Jon at fieroaddiction.com put it...

http://www.fieroaddiction.com/34dohc.html

quote Originally posted by Emc209i: The 2009 Honda Accord makes 271 hp off the lot.

...and the Locus Pléthore is 1,300-hp right off the lot - so what's your point?

The LS4 does cost more than the 4.9 to install no matter how you slice it (unless you have your own machine shop). You don't want to 4.9, fine, that is your opinion - no need to HARP on the topic.

quote Originally posted by thismanyfieros: thanks for the drive offer tim , but if i did that she might put two and two together..women are kinda smart that way...lol..

Oh yea, it is suppose to be a surprise. Anyways PM replied to.

[This message has been edited by Mickey_Moose (edited 03-18-2009).]

quote Originally posted by Emc209i: My '95 DOHC was an interference motor.

How so? Non stock cams? I've worked on 2 95s stock engines for customers that I recall who did not get the 60,000 mile maintenence on the belts. Their belts went, at one in the 80 -90 thousand mile range the other at about 110,000 miles and no bent valves.

It is my understanding that only the 96-97 engines are interference engines but all other yrs 91-95 are not and it appears so with no bent valves from failed belts in customers cars I've worked on.

No completely stock rebuilt engine. Stock 95 cams. We phased the engine cam timing out about 45*, then tried turning it over the crank slowly with a wrench. There was obvious mechanical obstruction. We pulled a spark plug and could see the valved coming into contact with a piston. The earlier motors may very well be non interference, but for one reason or another, mine was.

A broken belt does not always result in valve carnage. It's very possible that the valves in your customers cars happened to recess before a piston was able to slam into one.

[This message has been edited by Emc209i (edited 03-19-2009).]

My opinion is to take a ride in a Fiero that has each engine you are looking at. Personal preference on how you want the car to "feel" is the biggest factor.
Both swaps have been done often and each swap has it's own "personality".

If I was deciding on which engine to swap between the two I would do the 3.4DOHC swap. I have rode in Fiero's with both engines and the DOHC Fiero appealed more to me. But like I said it's a matter of personal choice.

best of both worlds: 3400 block, fiero intake...
//www.fiero.nl/forum/F...2/HTML/075502-3.html

No, the 3800 is the best of both world. You need to get another intake, your engine is falling flat on its face after 3700 rpm. I bet money its the Fiero intake. That looks very similar to a 4.9 dyno sheet.

quote Originally posted by Emc209i: No, the 3800 is the best of both world. You need to get another intake, your engine is falling flat on its face after 3700 rpm. I bet money its the Fiero intake. That looks very similar to a 4.9 dyno sheet.

Yes, this motor has much more potential still untapped.

I have 97% of the torque of a 4.9 and more RWHP than a stock: TDC, 4.9 or 3800. So is it the best of all 3 worlds then?
200+rwhp is only a Trueleo and a tune away...

This is a dyno sheet of a stock TDC.



I'm not sure how you can say you have more rwhp. Your torque curve is falling off early, and your power isn't the greatest. I'm sure a TDC would outrun you, being you only have good power for 50% of the power band a DOHC has. Shifting at 4000rpm will only get you so far. A 3800 would be about the same. Like I said, you need to work on your upper end power. Ditch the Fiero intake.

EMC209i,

The dyno sheet you showed for the TDC states fly Wheel TQ and HP not RWHP or RWTQ. So the power at the wheels would be 15-20% lower? I believe the 3400 w/Fiero Intake sheet was at the wheels. I could be wrong though.

john

You are. That is power at both rear hubs. There is not 10-15% loss from the hubs to the wheels.

Here is a video of the dyno run that produced the above graph.
http://www.youtube.com/watch?v=8Z5_2suyVnc

Why waste you time on either swap when you can just put in the 3800SC and have all the power you need. And if you want a little more than drop pullies w/ supporting MODS. No you want have that V-8 rumble or that 7K rev but you will have a swap that will put the other 2 swaps to shame in the end. Not only performance wise but looks wise also(even though the DOHC can look sweet). I think those that think the 4.9/3.4 DOHC swaps are beast just haven't ridden in a Fiero with big HP. Anyone going from a 2.8 to a 4.9 for example will think the thing is a monster even though it falls flat after the RPMs go above 3K.


But just so my post stays on topic--I would do a 5 speed DOHC turbo before I went with the 4.9.

quote Originally posted by MstangsBware: But just so my post stays on topic--I would do a 5 speed DOHC turbo before I went with the 4.9.

One of these days I might have you put a 5 speed DOHC turbo in my GT... I'd do that over the 3800SC. Something about that 90 deg V6 I just can't get used to.

quote Originally posted by MstangsBware: Why waste you time on either swap when you can just put in the 3800SC and have all the power you need.

Why waste your time putting a 3800SC when you can have all the power you need with the correct sound, image and pedigree from a 3.4 DOHC swap?? Or, for that matter lets put a DOHC V8 with 180 degree headers so it sound like it should along with alll the power you need???

quote Originally posted by jscott1: One of these days I might have you put a 5 speed DOHC turbo in my GT... I'd do that over the 3800SC. Something about that 90 deg V6 I just can't get used to.

You can't afford a decent swap, remember. To many bills and kids.

ok guys i appreciate the banter but like i stated before i already have a 3.8sc car...this swap is for my wifes 88 coupe..she doesnt need a high maintenence engine...something simple and reliable is what is needed...the 4.9 falls right into that bracket...it has a nice rumble,some oommpphh -not too much though, dont wanna be spending my extra cash on new rubber every year...lol..and still has a bit of the wow a V8 in a fiero factor...the swap seems pretty straight forward and even I might be able to handle most of it..lol...thanks guys...tim

quote Originally posted by Emc209i: You can't afford a decent swap, remember. To many bills and kids.

I wish Cliff had an "Ignore" feature in the thread to keep the RFT trash out.

[This message has been edited by jscott1 (edited 03-20-2009).]

I've been driving my 4.9 for about a month now and love it. It has a great sound, and honestly has enough power to make me happy. Do I race it? No. Would not be good for me to race it in my town because of my standing here (not an ego thing...but I am a business owner and a youth director). Do the kids around town want to race? Some....but they know my stance on "street racing" and understand that I won't.

The 4.9 gives me plenty of the get-up-and-go that I need. I don't have to worry about being run over and I can easily pass the vehicles that I need to on my to Waco, Killeen, wherever.

I firmly believe that your wife will have no issues with a 4.9 and will be very happy.

quote Originally posted by jscott1: I wish Cliff had an "Ignore" feature in the thread to keep the RFT trash out.

I guess you'll just have to start thinking about what you say then, huh. I think you said it best.

quote Originally posted by jscott1: Someday when you grow up you might understand that.

quote Originally posted by Emc209i:

I had nothing personal against you until you sent me an obscenity laced diatribe, which I didn't bother to read.

You obviously have a lot of growing up to do despite whatever your physical age might be.

quote Originally posted by jscott1: I had nothing personal against you until you sent me an obscenity laced diatribe, which I didn't bother to read.

I don't care what your intentions were before you sent me the pm that warranted my reply, you've made them clear now. Watch what you say, because I'm not going to look the other way any more.

quote Originally posted by Emc209i: I don't care what your intentions were before you sent me the pm that warranted my reply, you've made them clear now. Watch what you say, because I'm not going to look the other way any more.

Compared to how much you looked the other way in the past?

quote Originally posted by jscott1: I had nothing personal against you until you sent me an obscenity laced diatribe, which I didn't bother to read. You obviously have a lot of growing up to do despite whatever your physical age might be.

I counted all of 2 obscenities in the entire "diatribe" since he posted in on RFT. And if you didn't read it, how do you know it was "obscenity laced?"

So he posts a PM about me on RTF...that's mature

Why don't you RFT outcasts go back and play over there and leave the adults here to have a friendly chat about Fieros?

[This message has been edited by jscott1 (edited 03-20-2009).]

Thanks for answering the question.

quote Originally posted by jscott1: So he posts a PM about me on RTF...

No, I posted the message in its entirety. Your original post followed by my retort. This was explained in the private message you deemed misfit for your understanding. Thus far, you are the only one who hasn't complimented its tact, because you refused to read it. And if you're upset about it; remember, you were foolish to send it in the first place.

And resorting to name calling, exemplified in the above post, only solidifies an image of immaturity.

quote Originally posted by Emc209i: No completely stock rebuilt engine. Stock 95 cams. We phased the engine cam timing out about 45*, then tried turning it over the crank slowly with a wrench. There was obvious mechanical obstruction. We pulled a spark plug and could see the valved coming into contact with a piston. The earlier motors may very well be non interference, but for one reason or another, mine was. A broken belt does not always result in valve carnage. It's very possible that the valves in your customers cars happened to recess before a piston was able to slam into one.

any engine can suffer bent valves if high enough rpm with failure of the timing gear ..as it is the 91 -95 engines provide much less a chance than 96-97 engines of suffering that since they are concidered non interference engines. The 4.9 mos likey will never suffer such a mishap due to its low rpm nature

will u 2 just keep it to the PMs? i personally dont care what you say to each other, so long as i dont have to deal w/ it.
can anyone tell me the cost of a 4.9 swap? that would be my personal preference as well from what iv read. i dont need to race my car, the V8 factor is nice, and apparently they r built like a tank. iv already put enough time into my fiero on simpler fixes then a blown header/valve repair.

quote Originally posted by Nohbdy: will u 2 just keep it to the PMs? i personally dont care what you say to each other, so long as i dont have to deal w/ it. can anyone tell me the cost of a 4.9 swap? that would be my personal preference as well from what iv read. i dont need to race my car, the V8 factor is nice, and apparently they r built like a tank. iv already put enough time into my fiero on simpler fixes then a blown header/valve repair.

information is always useful ..since you asked for it

I like the 4.9 its a torquey motor that moves a deville quite nicely so it will have no problem motivating a Fiero is a rapid fashion

I am going to have to vote for the 3.4 TDC. I am seriously impressed with the swap I just had done. I am going to take it to the track soon. I really hope to see 13s.

EMC209i,

Just curious, why does your dyno sheet say Flywheel Horsepower/Torgue then? I'm not sure what the losses would be from the flywheel to the wheels with our type of tranaxle, 5%-10%?

John

quote Originally posted by 88wht-t-top: EMC209i, Just curious, why does your dyno sheet say Flywheel Horsepower/Torgue then? I'm not sure what the losses would be from the flywheel to the wheels with our type of tranaxle, 5%-10%? John

It didn't appear to be coming from the flywheel in the video. Looked more like the wheel hubs. Which was echoed in his following post.

quote Originally posted by 88wht-t-top: EMC209i, Just curious, why does your dyno sheet say Flywheel Horsepower/Torgue then? I'm not sure what the losses would be from the flywheel to the wheels with our type of tranaxle, 5%-10%? John

I guess its best I just send you here

makes sense now, had not seen that post before. I was not questioning your statement, just a little confused with what I was reading. Will that dyno also do flywheel numbers?

John

Edit: never mind

[This message has been edited by MadDanceSkillz (edited 10-13-2009).]

I personally don't think a 3.8 sc 2 engine sounds bad at all, mine has a flowmaster 80 and a resonator and it sounds sweet in my opinion, I have also owned a 4.9 before and drove a stick shift powered 4.9 and one behind a automatic, The stick shift 4.9 was faster off of a line then the auto 4.9 But first gear in a izusu transmission is a waste plus I had soo many clutch issues I hated it after awhile, The auto transmission in a members car jeff's car made that little notchie back fiero haul arse, That little fiero was really fun to drive and I did not want to give it back to jeff after the 4.9 install hehe, I have also driven a 3.4 dohc engine out of a lumina but never in a fiero.


IF you want a fiero that requires no real maintance then do the 4.9 if you want a engine that has aftermarket do a 3.4 dohc engine I believe you will like either of the 2 engines (well atleast your wife) Actually now looking back and seeing it's going to be a female driver( No offense females) Your best bet would be a 4.9 hehe, Just becarful not to plant her foot too much on the gas or she will find herself in someones back bumper.

I can vouch for a 4.9 being able to take abuse, before I rebuilt one my 4.9 engines the oil cooler line busted and I had to drive it home a couple of miles with no oil inside it, The engine still ran good but I was rebuilding it anyway, And after taking it apart there was no damage or wear to the bearings.


So in all the 4.9 is a very forgiving motor if you screw up A 3.4 dohc engine is not and I never liked belts to begine with, I hate the one on my daily driver mitsu eclipse, Why in the hell do they have to have the BELT DRIVE THE WATER PUMP ALSO !!! I can see something getting stuck inside the water pump and tearing everything to shreds hehe.


The 3.8 sc 2 engine beats them both hehe, It has the torc of a 4.9 and the hp of a 3.4dohc engine, And when that blower starts whistling, LOOKOUT, It also does not take long for that thing to wind up, Mine starts boosting at 3200 rpm


That's why I dissagree with a 3.8 sc engine sounding horrible, nothing sounds better then a blower kicking in


So if your lazy like I am and hate doing maintance then do a 4.9 or if you want a engine that produces more hp go with a 3.4dohc engine but if you want all worlds then a 3.8 sc is best

[This message has been edited by 86fieroEarl (edited 10-14-2009).]