A GM 3800SC produces 240 - 260HP from the factory. While a naturally aspirated 3.5 Nissan makes 265HP. Why are American engines so much more inefficient than their foreign counterparts?

BTW I love American muscle but this has been a sore spot with me for quite a while.

American engine are way behing in technology. Common ones anyway. The 350 has been around since when? How about the 3800's... Didn't they start out as a truck engine a long time ago?

The USA and Canada are huge compared to most countries. Also fuel is relatively inexpensive.

The roads and driving styles favour a larger, lazy, torquey engine over a small high revver.

Edited for stupid speeling.

[This message has been edited by FieroBUZZ (edited 08-02-2003).]

I think the simple answer is to keep things simple.. It's a lot more simple (read: cost effective) to throw a 3.8L pushrod engine, and expect it to last forever, vs. a 1.8L dual over head cam/variable timing/high revving engine. At least, that's my take on it.

Oh yeah - plus, it's because of the market.. as they say, BIG SELLS. Would you rather have a 5.7L 240hp v8, or a 1.8L 240hp I4?

[This message has been edited by ryan.hess (edited 08-02-2003).]

quote Originally posted by Mastermind: A GM 3800SC produces 240 - 260HP from the factory. While a naturally aspirated 3.5 Nissan makes 265HP. Why are American engines so much more inefficient than their foreign counterparts? BTW I love American muscle but this has been a sore spot with me for quite a while.

The 3800 is a pushrod engine. The Nissan is a twin overhead cam engine. The U.S. manufacturers are slightly behind in this area only because they prefer higher torque engines. Think about this, a 5.7L V-8 pushrod in a typical F-body averages 330HP. But a Northstar V-8 is only 4.9L and is at 300hp. A 3.4L in a Grand Am puts out 175hp But a Twin overhead cam version of the 3.4L puts out 215hp. The overhead multi-valved heads have a lot more flow than any pushrod head so the power increases are greater. Many U.S. companies just now are coming out with OHC/ Multi-valved engines that have high power outputs. There have been many engines over the years that they have tried with good success, (Quad4, 3.4L TDC, Northstars, etc) That have high outputs. But in the U.S. they seem to like the "If it works, Don't change it" approach and continue to use pushrod engines.

We've got the technology - but American car buyers would rather buy big & comfy rather than high-tech.

But it can be done (and is). My other car is a 2001 Taurus SEL. Its 3.0 DOHC engine produces 200 HP in stock configuration; this kicks that Nissan's HP/Liter ratio in the tail.

However - if you think a Fiero is hard to work on you don't want one of these. It looks like the front clip is shrink to fit around the drivetrain. You can't see much less touch the rear bank of plugs and you should see where the alternator is on this thing...

Is there any difference in the way the engines are rated? In the musclecar wars of the 60's and 70's there were several different ways to rate horsepower. Some manufacturers simply gave hp at a lower rpm to get insurance companies off their case.
I think the 426 hemi was rated at a lower rpm than normal, just to appease the insurance gods.

TG

Gas is so much cheaper here than in Europe (try 79 pence a litre in Britian or about $4.70 US a gallon).

Europe has had a long history of high fuel prices and as a result they have opted for more efficient engines and weight savings. We have been able to use older technology as fuel milage is not a real issue. As a result the complex, expensive engines are not as much in demand. Adding displacement is cheaper and ultimately more reliable than adding 2 more valves per cylinder.

We like our V8s for its image and familiarity. As a car company, why introduce an unfamiliar engine with a higher price to a public who like what they have? The ultimate goal of a car company is to make money. Imports sell to the world. The U.S. and Canada are just a part of it. The Big 3 market mainly to us.

Look at the resources the BIG 3 have in the world. They participate in the design and production of many of the famous European and Japanese makes (e.g. don't forget that Chrysler/MB once owned Lamborghini, the Ford/Janguar connection, GM/Lotus and on and on). They market the types of engines you mention to a public that demands them. When the North American public demand such an engine, it will roll of the assembly line.

Next time you go to a show, note the cars that command respect by MOST of the population, a turbo 4 or a small block Chevy?

My daily driver is a 2000 Dodge Dakota.It has a 4.7 SOHC V8 and a 5 speed. It has 235 hp. I do think it might possibly be one of the fastest trucks you can buy. If it had wings I swear it would fly. Next time you a see an american made V8 pull up to a light next to Any import be carefull who you bet on. Even though my truck is overhead cam and fast. American push rod engines have dominated EVERY type of racing there has ever been any time they wanted to. I love my 2.9 engine in my Fiero and the 467ci pontiac in my Trans am (450hp and never gets upset on 105 degree days and laughs at WRXs to the tune of 12.9 sec. 1/4 )

Anything they can do, we can do better. in 1990 we had a 3.4L DOHC that put out over 270 horses. However it was then cut down to 200 for the production run because of transmission issues. That VERY rare version of the motor was still a smaller and more powerful engine then is nissan's 3.5, and were talking about 13 years ago. Our Quad 4 HO is comparable, even roughly equal to most high end imported 4 cyls and there is always the Northstar to think about. GM is also not exactly playing on the same field as the imports. GM is a cheepo company always sacrificing things (many of the times, its engine power) for one reason or another in the name of cost or quality. What I am saying is, and Im using the Quad 4 program as the perfect example, after the 89-90 motors GM decided to spice the engine up alittle, to the tune of about 180 horses. But for some reason in 94 they cut the motor down to 160 horses, smaller ports, weaker cams, and then in 96, balance shafts to make it more quiet and vibration free, at a sacrifice of horsepower. In the end, I would say that GM has the technology and the ability to make smaller and more powerful engines then the imports, but don't care to.
Also, you have to consider the fact that GM still uses pushrod engines. Why? simply put, our cars are heavy and torque makes up for that, and pushrod engines make good torque. however, we lose out on horsepower because pushrod engines spin slower and horsepower is a combination of torque and RPM's. And latley I think GM is starting to wake up to the fact that you pointed out, about how nissan's kicking a$$ in the numbers department, so GM released the new 3800 supercharged to put out 260 horses as opposed to nissans 255. At least, thats how it appears...

Alitte thing I have to point out about horsepower. Like I said before, horsepower is a combination of torque and RPM's. And I mean that on a mathematical level.

Torque X RPM's / 5252 = Horsepower.

My point is, Look at a motorcycle engine.
lets just say that a good Japaneese style bike may have 120 horses, and has to rev to 11,000 RPM's to hit 120 horses. That equates to 57 lb ft. of torque. Not impressive at all. Imagine how slow your car would be once your clutch has engaged, that climb to 11,000 RPMs would be painful. And of course since the displacment on that engine is so small, the power to displacment ratio is huge, but you still aren't going to go fast. My Iron duke only had 92 horses, however it had 120 lb ft. of torque. Ill take that any day over that 57 lb ft from the motorcycle engine. (unless I expect to keep the motorcycle at 11,000 RPMS all the time)

I think that pretty well sums up MY view on this issue.

------------------
84 Indy fiero Quad 4 HO (almost done!!)
85 2m? Getting parted out soon
Silver 88 GT, Newest addiction.

quote Originally posted by Mastermind: A GM 3800SC produces 240 - 260HP from the factory. While a naturally aspirated 3.5 Nissan makes 265HP. Why are American engines so much more inefficient than their foreign counterparts?

They aren't. GM has been reluctant to go to DOHC engines across their vehicle lines probably due to service and reliability issues. When was the last time you have seen a pushrod engine in for a new timing belt? Unfortuneately, people who bought the 3.4 TDC/DOHC equipped cars back in the 90's didn't think they needed a timing belt changed either and look how that turned out. I have come to recognize GM as the big elephant that never forgets; well, almost never.

Horsepower sells cars but Torque wins races. In general, American cars are heavier and therefore they require more torque. I say let the little Honda have its 9000+ RPM Vtec engine; when he gets rearended by an SUV do you think that thin sheet metal is going to protect him better than detroit iron? I think not.

------------------
1987 Fiero Coupe 3800 Series II Intercooled Turbo
1987 Trans Am GTA 5.7L Superram 4L60-E
1985 Fiero SE 2.8 (soon to have an L36)

Fiero-related Conversions Performed:
1985 SE 3800 Series 1 SC 4T60-E
1987 Coupe 3800 Series II Turbocharged 4T60-E
1987 SE 3.4 TDC 5-speed
1984 Coupe SBC V8 non-OD to 4T60 OD swap, electric power steering install
1985 SE 3800 Series II Supercharged 4T60-E

http://dtcc.cz28.com

We can hate ricers all day long, but they made us grow up. They were using twin overhead cam 4 valve, FI, turbo, SC since WWII, but it never made it to manufacturing. Why? American corporations have been allowed to feed us crap until foreign competition made them grow up. The crux was in the mid eighties where American autos hit all-time lows.

As for performance, even low-end Jap cars have twin OH cams w/hemi combustion chambers. Jap bikes have had TOHC hemis since the 86 GSXR, hence huge perfomance.

Oh great. As soon as I saw the subject line, I was instantly reminded of this little innocent thread started by Johnny K a few years ago: Why American Engines Suck
If you guys haven't read it yet, there's a couple of interesting points mixed in among tonnes of junk. Kinda like here (j/k)

Anyway, I'll perhaps post my opinion on the us vs. import engines debate later.
I'm off to bed now

Regards,

Kris

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

Little, Yellow, Different New sig pic with 17's coming soon!

[This message has been edited by Kris Duck (edited 08-05-2003).]

quote Originally posted by vinny: My daily driver is a 2000 Dodge Dakota.It has a 4.7 SOHC V8 and a 5 speed. It has 235 hp. I do think it might possibly be one of the fastest trucks you can buy. If it had wings I swear it would fly. Next time you a see an american made V8 pull up to a light next to Any import be carefull who you bet on. Even though my truck is overhead cam and fast. American push rod engines have dominated EVERY type of racing there has ever been any time they wanted to. I love my 2.9 engine in my Fiero and the 467ci pontiac in my Trans am (450hp and never gets upset on 105 degree days and laughs at WRXs to the tune of 12.9 sec. 1/4 )

Vinny my point is, foreign car makers seem to consistently get more horsepower with less displacement than American car makers. Your post is a good example. Foreign car makers would probably get at least twice the HP from the displacement of your two engines than the numbers you quote as American.

BTW this is not a bash American engine thread. I ask this to try and understand why it's this way and hearing other opinions is a good way to do that.

Hows the Torque on them foreign engines? They maybe making more HP per liter, but it really sucks when it doesn't come on until 4,000+ RPM.

Why?

I think it is differing styles.

MOST of WE Americans (the majority) like to jump in the car and go. Hell, we get pissed if we have to get gas!

We like quiet engines so we can blather with Maggie and Harry about the last canasta game. We are not comfortable if we feel the road. The interior is climate controlled and the vehicles that sell the most are the ones that have seats like our sofa at home. We travel 20-50 miles and feel like we've gone a long way. To actually HEAR the engine? Oh NO! Our Automobile is more of an extention of our living room than it is a "motor vehicle". And most of us do not feel comfortable in anything less than 200 inches long and under 3000 lbs.

With the Automatic Transmission we love (recent Harris poll had 65% responding that they would NEVER buy a manual transmission car!!), the roads we drive on, the way we drive, the options we like; What kind of engine does best in this application? a big lazy v8 (or now v6 like the 3800 series II) that is "torque heavy".

Compare that with countries where gasoline is 4x as expensive (and we gripe about the high cost), "Road taxes" payable at registration are based on size of car, weight, etc with hefty penalties for 'larger vehicles' and you find that there is every incentive for people in Europe and Japan to favor smaller cars with highly evolved (read highly volumetric efficient) engines. They've learned to love the wind of an engine cause that is their control of power.

Why American engines torque heavy and not HP Monsters? Not because of less technology. It is a concious choice.

It is because where and how Americans drive; torque, not horsepower, is the key.

quote Originally posted by Mastermind: Your post is a good example. Foreign car makers would probably get at least twice the HP from the displacement of your two engines than the numbers you quote as American.

Go look at Toyota's DOHC truck engines to compare.

If you want to talk about power vs. size why limit your self to the piston engine...remember a wankel rotary in the 93-95 Rx7 put out 260 hp out of 1.3 liters. Now the Rx8's 1.3 is rated at 250 naturally aspirated. That is power to weight...unfortunately it is all horsepower and little torque..but geared right they are quick.

Also someone mentioned above the mixture of domestic and american. Izuzu and GM have been in bed for a while, Mazda is 33% owned by Ford...etc
How many dodges have Mitsubishi engines?
Nate

Double the displacement on a rotary to be fair...
http://travel.howstuffworks.com/rotary-engine.htm

quote Originally posted by Manic Mechanic: Hows the Torque on them foreign engines? They maybe making more HP per liter, but it really sucks when it doesn't come on until 4,000+ RPM.

I love this argument. Although true, the lack of lowend torque can be overcome with gearing. Explain how stock GSXR's, Ninjas, etc have pathetic ; lowend torque, yet the big bores go 1-60 in a hair over 2 seconds. The Harley argument is that Jap bikes are junk due to no lowend torque, my reply is then the Harley should easily beat he jap bike, especially off the line.

If you take a big bore, short stroke motor, rap it to several thousand RPM's, and then drop the clutch, you will realize what torque is. This is actually the inertia created from the spinning mass, but none the less still torque. I also love the old motor-heads that mimic..."there's no replacement for displacement." Uh, yea. It's called stroking, TOHC, Hemi, FI, turbo, SC, etc. They will invariably reply with something about using that technology with larger displacement. That logic might work with a factory engine that sits all day, but with a moving vehicle the saving s in weight are more important and more usable with a lighter engine.

I love the LT-1 more than any other motor I've driven, but why does it suck to have the torque/hp not available until 4k rpm? It takes more skill to drive a vehicle, especially a M/C with the engine rapped up in the corner, as it is more volatile, but it's nice to be right before the powerband as you're pulling out of the corner.

quote Originally posted by I'm Back: I also love the old motor-heads that mimic..."there's no replacement for displacement." Uh, yea. It's called stroking, TOHC, Hemi, FI, turbo, SC, etc.

Stroking == displacement

What the heck is TOHC?
There is no replacement for displacement. A 4 cylinder is better for and Elise or MR2 Spyder, but a turbo 4 isn' going to be much fun in Vette, because of the extra weight it would have to move. The Vette needs abig engine with low RPM torque to be responsive.

Euro motors are smaller and more effecient that american motors because insurance is based off of displacement/HP in some places. Its cheaper to own a 1.8T w/220HP, vs a 3.8 n/a w/205HP. Combined with gas prices, it sounds logical to have smaller engines

BTW, if you look at GM's new(er) DOHC 4.2L I6, you will notice you dont have to rev it to get power. 80% of the avail torque hits at below 2000rpm.. That makes for a pretty flat torque curve. Too bad this engine is sooo large, it'd make a great swap!

Edit: Look at GM's new engines.. they are all DOHC afaik. GM might be coming for a ride on the bandwagon..

James Z

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

- 2.8v6, 5spd
- no cat, msd ignition/coil, K&N

[This message has been edited by SplineZ (edited 08-03-2003).]

quote Originally posted by Will:

"Stroking == displacement"

It amounts to a loss or gain of displacement, depending upon whether you increase or decrease the stroke. But it also changes the dynamics of the engine, as with potential rpm and cam dynamics and a multitude of other attributes. I knew someone would pick up on that when I referred to displacement. I relize it changes displacement, but it changes the other attributes of the engine more drastically.

"What the heck is TOHC?"

Twin overhead cam. Is it not written in the language you're used to?

"There is no replacement for displacement."

Don't tell me you're a motorhead, Will. There is a replacement. What that expression means to me is that a 454 will beat a 350, will beat a 305, etc.... To look at it the other way, what if you are constrained by volume of engine compartment, weight, or any other necessity? The best example is the good ole 350. An LT-1 is way ahead of a steel 350 from a Chevy Caprice. An LS-1 is way ahead of an LT-1. You have injection, better flowing heads, better ignition, better cooling (reverse flow), and likely other improvements that I can't think of right now. So the replacement is technology with the same displacement, making unnecessary the need to increase displacement. Now a person that wants to argue the absolute value of pie could continue to say that you could take that technology and apply it to engines with a greater displacement. So that person could chase their tail into oblivion with that logic and never reach an intellectual conclusion. Since motor vehicles are constrained by size, weight, and drivability, throwing a big block into a road car might not be feasible as it would be in a dragster. So with that, yes, there are replacements for displacement.

"A 4 cylinder is better for and Elise or MR2 Spyder, but a turbo 4 isn' going to be much fun in Vette, because of the extra weight it would have to move. The Vette needs abig engine with low RPM torque to be responsive."

Ok, let's not go apples/oranges with the Eclipse/Vette scenario. Let's go Vette LS-1/Vette 454. We're going high tech 350 w/405 HP stock that has all aluminum block/heads, 6 bolt mains and all the toys versus a big, heavy torque monster. So now your argument is that we could use that technology on a big block. Sure, and the rpm range would be less, which might not be a huge deal. So we use rods that cost 3k/set and pistons that cost 2k to keep the same rpm potential. Now we have reliability issues and our tranny isn't tough enough to handle the torque, so we need to beef that up gaining us more poundage. Hey, why don't we all mortgage our houses and go to Alan at CHRFAB and get one of those 1,200 hp N*'s fro 35k? See, inside a vacuum anything is possible and everything is feasible, but in real life it doesn't work, so there are replacements for displacement. Inside a vacuum the age-old cliché is correct, because you can apply the technology to the larger engine every time and gain more hp, but it isn't realistic when applied to road vehicles.

[This message has been edited by I'm Back (edited 08-03-2003).]

My BMW 525i (1993) straight 6 cyl 24v pushes out 193BHP.

My Wifes VW Vento GL (called a Jetta in the US i think) knocks out 136BHP, and its only a 1.8 litre 8 valve.

By comprassion my neighbour has just brought one of the new europeon Super Diesels. A VW Golf TDi PD 150.
1.9 Litre 4 Cyl Diesel pushing out 150BHP. 0-60 in 6.8 seconds and 142mph top speed!!. Not bad for an oil burner !.

By comparrison to the Fiero, back in the 80's i had a Renault 30TX (1979) , this car had a 2.7L V6i engine very similar in construction to the Fiero V6. But it pushed out 170BHP at 5500 rpm.

Although in General european engines are more powerfull, they do not produce the lovely sound that a USA V6 or V8 produces.

PS: At current UK petrol prices, 1 Gallon of Super Unleaded (98 Octane) is $6.34 US Dollars a gallon !!.

------------------
Regards,

Paul Taylor, England.
85 GT Notchback, 2.8 V6, 4 speed manual. Custom made Tubular branch exhaust manifolds with true twin 3in exhaust system. No CAT, No EGR. No Crossover pipe. ADS Road Race SuperChip & 160 deg stat. Poly bushes all round. Lowered 2 inches. 16" alloys with 225/45 rubber. 0-60mph in 5.5 sec.

www.fieroforum.co.uk/Paul85gt.htm

quote Originally posted by I'm Back: I relize it changes displacement, but it changes the other attributes of the engine more drastically.

No, it changes displacement more. Yes, a 383 takes a slightly different cam than a 350 to optimally perform, but even with a 350 cam, the 383 will make 10% more torque everywhere in the RPM range, assuming certain caveats, like heads that will support the extra airflow, etc. None of the effects of rod ratio or piston speed or any of the other factors combined are going to amount to 10% difference.

quote Twin overhead cam.

I thought of that after I posted. No I'm just not used to hearing it. Are you from Europe?

quote Don't tell me you're a motorhead, Will. There is a replacement.

We're looking at things from different angles. An SR20DET in a Corvette could equal stock LS6 HP and TQ, and probably even acceleration performance, although not at the same power level due to powerband characteristics and gearing, but the SR20DET will NOT be able to go down the highway at 80 mph turning 1800 RPM like the LS6 can. The Corvette needs that low crusing RPM to get good gas mileage. Don't tell me that the smaller engine will get better mileage turning faster, because it won't. Compare the EPA highway mileage figures for a Corvette and S2000. The Corvette gets better highway mileage. Displacement kicks butt.

quote An LT-1 is way ahead of a steel 350 from a Chevy Caprice.

Hate to burst your bubble, but Caprices came with LT1's.
LT1's had reverse flow cooling, but I don't think LS1's do. At least you realize that there's technology in an LS1. Most dismiss it because it uses pushrods.

I read an article in a magazine a while back about a guy who didn't think his C5 was responsive enough in 6th gear, so he went to a good deal of trouble to swap in a Vortec 7400 engine. It eventually fit and he liked it much more because it had 150 ftlbs or so on an LS1 at low RPM. Big block in a C5's been done, and there are NO driveline issues.
From a production standpoint, there wouldn't be much difference in producing an LS1 vs. a production high performance aluminum big block. Just the difference in materials costs, because the overhead is going to be the same either way.

The C5R uses a 7.0 litre LS1. Extra displacement works for them.

It also works for the guys who stroke RB26DETT's to 3.0 litres and beyond.

I was referring to packaging considerations when mentioned the Elise (as in Lotus, not Eclipse) or MR2. A v8 would not be a good choice for these cars because of engine compartment size, vehicle weight and balance, etc. A turbo 4 would be a better choice for these vehicles. A 4 cylinder's lack of low RPM torque probably would make the cars easier to launch hard as well. As I explained above, for a Vette, displacement makes more sense.

[This message has been edited by Will (edited 08-03-2003).]

october i bouhgt a brand new peugoet 206, it has a 1.4l I4 common rail turbo diesel, it produces 68 horses and ~90ftp of torque. it runs 27km/liter. or about 64miles a gallon.

yearly registration taxes on this one are about 150$, on the fiero taxes are about 610$

another big difference is the reliability. take the mercedes engines, they last forever and are rated low HP. same size jap engine would probably only last 1/3rd of the milage compared to the mercedes, but would likely have 1.5 or 2 times the HP

hans

In Japan (for instance) The vehicles are taxed according to the displacement. A 1.2 is affordable, 1.4 is higher, 1.6, 1.8, 2.0
2,2 etc. When you get above 1.8, It falls into a priemiem tax. So they try to get as much horsepower out of the 1.6 and 1.8 that they can. The engines are more expensive to build for that kind of efficiency, but the extreamly high tax is hard to sell on the larger displacements.

quote Originally posted by Mastermind: A GM 3800SC produces 240 - 260HP from the factory. While a naturally aspirated 3.5 Nissan makes 265HP. Why are American engines so much more inefficient than their foreign counterparts? BTW I love American muscle but this has been a sore spot with me for quite a while.

For the same reason the 3.5 only makes 210hp when Nissan throws a supercharger on it and sticks it in their trucks?

Somehow this has turned into a Torque vs. Horsepower thread.

First of all, dumping the clutch at XXXX RPM does not produce torque. That is called inertia of the rotating engine components and it is also very hard on drivetrain components. Besides that, gearing cannot compensate for a poor torque curve.

Adjusting gearing is a nice try in an effort to overcome a torque deficientcy, but you only have so many gears in an automobile's transmission and your DOHC engine is going to have to spin higher (and work a lot harder) than my pushrod engine going down the highway in order to maintain a certain speed with headwinds and hills. While this may not seem like it matters a whole lot, I don't see as many 200,000+mi DOHC'ers on the road as I do 3800's and 350's. (of course, a lot of that could also be due to the fact that the thin import sheet metal rusts out quicker than detroit iron)

BTW, what I do see is a lot of DOHC equipped cars running around burning oil due to worn out piston rings or cylinders. What causes this? Extended high RPM operation. No matter how well an engine is built and how good the parts are, there are only so many times that piston can travel up and down in the cylinder before things start to wear out. Believe me that this is something that GM and other automakers have looked long and hard at.

GM is not behind the times. They have tried a lot before many other automakers had. AWD Pontiac 6000 in the late 80's. Digital instrument clusters. Computerized HVAC and radio controls. OHC engine back in the 60's. DOHC V8 engine in the Vette in the late 80's. So what if my 95 Beretta 2.2 pushrod engine only makes 120HP, it makes 130tq as well. A comperible import engine may make more HP than I do, but my heavier, more inferior american car with the archiac pushrod engine has more import kills than I can count on various body parts. Why? TORQUE. Imitated, but can't be duplicated.

quote Originally posted by Will: Hate to burst your bubble, but Caprices came with LT1's. LT1's had reverse flow cooling, but I don't think LS1's do. At least you realize that there's technology in an LS1. Most dismiss it because it uses pushrods. I read an article in a magazine a while back about a guy who didn't think his C5 was responsive enough in 6th gear, so he went to a good deal of trouble to swap in a Vortec 7400 engine. It eventually fit and he liked it much more because it had 150 ftlbs or so on an LS1 at low RPM. Big block in a C5's been done, and there are NO driveline issues. From a production standpoint, there wouldn't be much difference in producing an LS1 vs. a production high performance aluminum big block. Just the difference in materials costs, because the overhead is going to be the same either way. The C5R uses a 7.0 litre LS1. Extra displacement works for them. It also works for the guys who stroke RB26DETT's to 3.0 litres and beyond. I was referring to packaging considerations when mentioned the Elise (as in Lotus, not Eclipse) or MR2. A v8 would not be a good choice for these cars because of engine compartment size, vehicle weight and balance, etc. A turbo 4 would be a better choice for these vehicles. A 4 cylinder's lack of low RPM torque probably would make the cars easier to launch hard as well. As I explained above, for a Vette, displacement makes more sense. [This message has been edited by Will (edited 08-03-2003).]

“No, it changes displacement more. Yes, a 383 takes a slightly different cam than a 350 to optimally perform, but even with a 350 cam, the 383 will make 10% more torque everywhere in the RPM range, assuming certain caveats, like heads that will support the extra airflow, etc. None of the effects of rod ratio or piston speed or any of the other factors combined are going to amount to 10% difference.”

Oh, so head design must accompany larger displacement for the larger displacement to be afctor? So there is a replacement for displacement you’re saying. How about the better heads on a 350? Perform better than a 350 with stock heads? Yep. So you’re saying that an engine, not necessarily 350 to 383, but a small block compared to a big block will have the same rpm potential? Gonna turn a 454 to 9,000 rpm easily?

“I thought of that after I posted. No I'm just not used to hearing it. Are you from Europe?”

Because I write TOHC instead of DOHC and you don’t like it? I think I have read TOHC on a Jap 4 banger. You know I’m not from Europe. Splitting hairs about the terminology of TOHC vs DOHC is like correcting errors of syntax in a post. You’re a smart guy, you knew what I meant, just didn’t like the way I wrote it.

“We're looking at things from different angles. An SR20DET in a Corvette could equal stock LS6 HP and TQ, and probably even acceleration performance, although not at the same power level due to powerband characteristics and gearing, but the SR20DET will NOT be able to go down the highway at 80 mph turning 1800 RPM like the LS6 can. The Corvette needs that low crusing RPM to get good gas mileage. Don't tell me that the smaller engine will get better mileage turning faster, because it won't. Compare the EPA highway mileage figures for a Corvette and S2000. The Corvette gets better highway mileage. Displacement kicks butt.”

Who in the hell is advocating putting a 4 banger in a Vette? Who was talking gas mileage? You’re intentionally taking my points out of context to attempt to persuade some that displacement is king. I’m talking a steel 350 from 1978 versus an LT-1 from 1995 versus an LS-1 from 2000. Same displacement, way different performance based upon technology that REPLACES the need for increases in displacement.

I wrote: An LT-1 is way ahead of a steel 350 from a Chevy Caprice.

“Hate to burst your bubble, but Caprices came with LT1's.
LT1's had reverse flow cooling, but I don't think LS1's do. At least you realize that there's technology in an LS1. Most dismiss it because it uses pushrods.”

Hate to burst yours, but they made Caprices before the introduction of the LT-1. The example I was referring to was that an old, nasty steel block/head 350 is pathetic compared to an LT-1, which has essentially the same lower end. I know the LT-1 has reverse flow cooling, I’m not sure about the LS-1. Of course I realize there is technology in the LS-1, there is also a lot of head technology in the LT-1. The presence of pushrods merely means it’s more difficult to get high rpm’s from the motor.

“I read an article in a magazine a while back about a guy who didn't think his C5 was responsive enough in 6th gear, so he went to a good deal of trouble to swap in a Vortec 7400 engine. It eventually fit and he liked it much more because it had 150 ftlbs or so on an LS1 at low RPM. Big block in a C5's been done, and there are NO driveline issues.”

OK, and weight wasn’t an issue apparently. I’m not knocking the big block Vortec in any way, what a sweet motor, but there are other ways to get hp than with increased displacement. For a guy that went N* to be advocating large displacement, heavy motors, I have questions. Not only that, but you went 5-speed at least in part to keep weight down, so you know weight is a huge issue.

”From a production standpoint, there wouldn't be much difference in producing an LS1 vs. a production high performance aluminum big block. Just the difference in materials costs, because the overhead is going to be the same either way.”

Ok, talk GM into it. As for driveline issues, the article is hearsay and the swap is new so we’ll see what happens to it, or rather we won’t.

I was referring to packaging considerations when mentioned the Elise (as in Lotus, not Eclipse) or MR2. A v8 would not be a good choice for these cars because of engine compartment size, vehicle weight and balance, etc. A turbo 4 would be a better choice for these vehicles. A 4 cylinder's lack of low RPM torque probably would make the cars easier to launch hard as well. As I explained above, for a Vette, displacement makes more sense.

Oh, I thought you misspelled “Eclipse.” There are two schools of thought in reference to displacement: There is a replacement or there isn’t. The sides will never concede to the other. It’s kind of a chicken/egg scenario, in that you can take a small block and juice it up to the numbers of a big block. But then you can say that the same technology could be used on a big block. With $800 in cams and springs, your N* will turn 8,000 rpm w/a stock lower end and will last well too, can you say the same about a big block vortec? So yes, there is a replacement for displacement.
I thought the motor head mentality went out years ago, as it used to be the primary factor when determining engine output in the 70’s, but since then, technology has rebdered big block performance from a small block.

Wasn't one of GM's most powerful and highly sought after engines a 302?, made in the 70's? It had aluminum heads making incredible HP with a redline around 7 - 8000? Now if that's the case clearly displacement alone is not the answer.

BTW And didn't that engine produced more HP than the 350?

[This message has been edited by Mastermind (edited 08-04-2003).]

quote Originally posted by Will: It eventually fit.

HAHAHA

quote Originally posted by Darth Fiero: BTW, what I do see is a lot of DOHC equipped cars running around burning oil due to worn out piston rings or cylinders. What causes this? Extended high RPM operation. No matter how well an engine is built and how good the parts are, there are only so many times that piston can travel up and down in the cylinder before things start to wear out. Believe me that this is something that GM and other automakers have looked long and hard at.

What you're failing to realize is that there is actually less wear on a short stroke engine at a given RPM. Think about the linear travel of the piston, which travels farther, a SBC or a little Honda? The SBC obviously travels farther, which produces more friction, this leads to more heat and wear. The same goes for bearing surfaces. If you have a large bearing (Large displacement American engine) as opposed to a small bearing (ever seen the rods and mains on an import?), which is going to produce more friction? The larger bearing surface is. This is very simple physics, and I can't believe someone as educated as you claimed to be in the last thread you were involved with wouldn't know that. Would you like this Electrical engineer (nope, no degree in "performance automotive") to go on and explain volumetric efficiency and squish band to you as well? How about indicated mean effective pressure? I work with people who also have the NIH (not invented here) attitude. I hope you outgrow it.

Edited for more combustibility

[This message has been edited by bushroot (edited 08-04-2003).]

Emissions!

------------------
86-2m6

Some people love to spin to 9K rpm, while others really don't get their jollies off it.
Neither type of engine is "superior" to the other. Some engines are just better for some people, while others are better for others.

I will say this though:
The Z34 Monte Carlo had the 3.4L DOHC motor until 1998-1999 when it was replaced with the L36 (3800 N/A). The 3.4 DOHC was a great motor, don't get me wrong, but most people (IE those who spend money on cars) don't like putting their car in the shop every 60K miles for a new timing belt, when the other car with the pushrods doesn't make them do that.
The 3.4 DOHC was putting out 215HP/215TQ.
3.8 N/A for '99 puts out 5 less HP, but more torque.

So To Respond To The Original Question
American motors put less power/liter out because they don't have to. Anytime they try to put out more power/less displacement, reliability goes to hell and the consumer buys elsewhere.

There is a reason why the current 3.8 S/C is only at 260hp (now) and theres only 1 reason.... Transaxle reliability. A 3.8 S/C could produced a safe and reliable 350hp and still get 25mpg. Why doesn GM do this? They dont trust they're transaxles to be put up against this much power. Those jap engine sdont have as much torque as the 3.8 and the transaxles are going to be under less stress

Just to set this out now, HorsePower makes no difference here, everything is about Torque. Horsepower sells cars, Torque wins races.

Currently GM and Ford are teaming up (yes you hear me right) to develope a 6 speed automatic transaxle that will be able to hold up to the torque that american engines produce

Now with that power per liter crap....thats just it, crap. remember what i said about horse power and torque. For the sake of arguement someone might say that they're honda makes 100hp per liter, yet it may be a 1.6 liter engine. Thtas still only 160hp. Imagine if all GM engines were like that. A 19 year old at the wheel of a 570hp camaro or trans am. A 810hp Silverado rolling off the line, an old man picking up his 460 horse cadillac from the dealer...

Theres more room to make reliable power with a larger displacement engine. With just say a 350. You can have anywhere from 100hp to 1000hp (remember im leaving torque out for now).

There is the ability to make your engine to equal 100hp or more per liter, but then youd have a 810hp SUV to give the wife to get the kids from soccer practice

In the honda its 160 puny horsepower, maybe enough to get you down the line in 16 seconds. in a Camaro, even though its not 100hp per liter, its still plenty, 325 horses to get you down the line in the low 13's. Having high horsepower to the liter is just not needed. There is no replacement for displacement. Anything that can be done to get more power out of a small displacement engine can be done to a higher displacement engine yeilding even better results

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


--Adam--
1987 Blue GT 5-speed
IM AOL: FieroGT5speed

[This message has been edited by GTFiero1 (edited 08-04-2003).]

quote Originally posted by Mastermind: Wasn't one of GM's most powerful and highly sought after engines a 302?, made in the 70's? It had aluminum heads making incredible HP with a redline around 7 - 8000? Now if that's the case clearly displacement alone is not the answer. BTW And didn't that engine produced more HP than the 350? [This message has been edited by Mastermind (edited 08-04-2003).]

The Sports Car Club of America (SCCA) had started the Trans Am series in 1966, and the Mustang had been dominating the Group II class (compacts under 116-in. wheelbase with an engine displacement limit of 305 cu.-in.).
In the early days of Trans Am, the racecars were actually based on street models, and the field included such Europeans as the Alfa Romeo Guilia and the Porsche 911. To qualify the Camaro, Chevy quietly offered an unadvertised "Special Performance Package" option in early 1967. The division produced only 602 Camaros with the new option, which featured a 290-hp 302 cu.-in. version of the small block exclusive to this package.
The 302 came out in 67 in the first year Camaro with Z28 as a 2 bolt and continued though 1969 as a 4 bolt main with 290HP. It was a 327 block with a 3.00 inch stroke 283 crank. In 1969 you could order a crossram manifold with 2 4barrel Holleys and headers with the Z28. They came in the trunk for you to install. With that combo the 302 would put out 450 HP @ 7000rpm but wasnt streetable

I had one of these with the Crossram and let me tell you , It would rip your head off but only if you kept it hammered. It had a Muncie close ratio M22 rockcrusher and a 4.10 limited slip positraction differential.It wasnt very streetable with a very choppy idle (2000rpm) and low torque and no vacuum at idle but it would run low 12s and high 11s in the quarter mile.

I would love to build a 283 with the 302 cam specs in a roller grind along with a hi RPM valvetrain. AFR 220s with titanium valves. Then use the 3.91 geared Getrag from a 91 W41 Cutlass in a Fiero.

I think the most sought after motor in the late sixties early seventies was the 427 copo L88 with open chamber aluminum heads and the 69 ZL1 COPO 9760 all aluminum 427 that came in 69 1969 Camaros and only 2 1969 Vettes total. Conservatively rated @ 430hp,it was more like 500. The most sought after motors of the early 70s would be the LS6 454 and the LS7 454 along with the LT1 350. The ratings were 450, 465, and 360 respectively in the 1970 year. 60s Vette with the FI 327 was rated at 375hp

[This message has been edited by Erik (edited 08-04-2003).]