Real Pontiac V8s

[MattC]

1973-81 was the last era for Pontiacs with real Pontiac V8s. The 1973/74 SD 455 & 1977-79 W72 400 Trans Ams got 1/4 mile in 13.56 & 14.6 seconds in Hot Rod magazine, 1973 & 1979 respectively.

1973/74 SD 455 (LS2) Trans Am

http://www.angelfire.com/mi/jamos1/index.html

1977/78 W72 400 Bandit style Trans Am

http://www.78ta.com/international.htm

Even the automatic 1981 turbo 4.9 Trans Am kicked butt when it got 16 seconds flat on ultra low octane gas and the Camaro Z/28 got 16.5, and a 4 speed Corvette got 17 seconds flat in Road & Track that year.

1980/81 Turbo Trans Am (LU8)

http://my.execpc.com/~steveb/transam/rehorn/page1.html

The magic of the classic Poncho V8s. 👍

 

[1X83Z]

Are you saying the current V8s aren't real Pontiac V8s? You're mad. They couldn't get any realer. One was developed by General Motors and Cadillac engineers for use specifically in Cadillacs beginning in about 1993 and the other was developed by Chevrolet solely for use in the Corvette, with its use an afterthought in the Chevrolet Tahoe (and then of course in the Chevrolet Camaro).

See? Obviously those are 'real Pontiac V8s.' I don't know what you're talking about.

 

[MattC]

There was a time, many moons ago, when Buick and, dare I say it, Oldsmobile, actually had their own V8 designs as well. And these were the most successful times for GM. Gee, do you think they need to have more variety, some original ideas and not just draw everything off Cadillac and Chevrolet? Hell, I don't know what Bob Lutz gets paid but I could have told them that for free. Maybe I'm giving off the wrong Vibe?

 

[1X83Z]

And these were the most successful times for GM.

It's not like they just stopped. There was a fuel shortage. Nobody wanted big GM V8s anymore. In a few decades, the same problem will occur. In fact, no-one will want any V8s soon.

 

[MattC]

What about a small efficient V8 of 4 liters with OHC? A 3 liter V6 and 4 liter V8 in a 3,000 lb rear drive pony car could be an alternative to the turbo Japanese imports.

 

[Joey D]

You couldn't talk someone, who's a die hard American V8 fan, in to a small effiencent V8. There is no replacement for displacement, remember that.

 

[1X83Z]

You couldn't talk someone, who's a die hard American V8 fan, in to a small effiencent V8. There is no replacement for displacement, remember that.

Certainly. And what's the point of having a 3-liter OHC V8 when a six-cylinder could do the exact same job? Really, it's having a V8 just to say you have a V8 when it has no excess benefit.

 

[MattC]

No, that's not what I said. I said that you have a new affordable rear drive coupe that weighs about 2,800-3,000 lb, and have as an engine option range a 2.5 4 cyl, 3 liter V6 and at the top of the range a 4 liter V8.
The old Trans Ams, and cars of their ilk, weighed close to 4,000 lbs and as a result needed their 6.6 liter motors to crank out enough torque to get them moving. An affordable 3,000 lb rear drive 4 liter V8 coupe is an alternative to something like a WRX, or a 2.5 turbo Skyline, and being only 3,000 lbs / 4 liters you would get around gas guzzler taxes.

 

[Duke]

None of the American V8s was worth a real diddley after 1972 at the latest, and really 1970 is the cutoff - before serious emissions restrictions. 1973-1983 V8s used more to do less than any other time. After 1972 you might just was well punch Fast Forward and skip ahead to about 1988 or so. This is why the current generation of Japanafanatics holds American cars in such poor regard: they don't remember the early days where the Big Three got it right, and they ignore the later days when the Big Three figured it out again.

 

[Lethalchem]

It's not like they just stopped. There was a fuel shortage. Nobody wanted big GM V8s anymore. In a few decades, the same problem will occur. In fact, no-one will want any V8s soon.

I disagree. As you pointed out in the above post, gas prices killed a lot of the performance motors, BUT they did not die. They have come back strong. In fact, the performance level of cars now, exceeds that of those older incarnations. There will always be a group that adores the V8. Nothing else in the world sounds like one. 👍

 

[Lethalchem]

You couldn't talk someone, who's a die hard American V8 fan, in to a small effiencent V8. There is no replacement for displacement, remember that.

I disagree with this as well. My 4.6l V8 equates to a tiny 281 cubic inches, yet it puts out 530hp and 560tq. That exceeds many "big block" numbers of the past. I consider myself an American V8 fan, and am very happy with this setup.

 

[Lethalchem]

Certainly. And what's the point of having a 3-liter OHC V8 when a six-cylinder could do the exact same job? Really, it's having a V8 just to say you have a V8 when it has no excess benefit.

Obviously you've never owned one, if you honstly believe that statement.

 

[Lethalchem]

None of the American V8s was worth a real diddley after 1972 at the latest, and really 1970 is the cutoff - before serious emissions restrictions. 1973-1983 V8s used more to do less than any other time. After 1972 you might just was well punch Fast Forward and skip ahead to about 1988 or so. This is why the current generation of Japanafanatics holds American cars in such poor regard: they don't remember the early days where the Big Three got it right, and they ignore the later days when the Big Three figured it out again.

??? I don't even know where to begin with this one.

The modern American V8 puts the old iron to shame. Sorry. Check the numbers. The modern V8's put down more power, run faster track times, are more relaible, don't overheat, and get better gas milage than any of the old school muscle.

 

[Duke]

The modern American V8 puts the old iron to shame. Sorry. Check the numbers. The modern V8's put down more power, run faster track times, are more relaible, don't overheat, and get better gas milage than any of the old school muscle.

No argument from me. The original poster was considering the days from 1973-1981. I'm saying nothing in that era after about 1970 was worth considering until you get to the much newer engines. Perhaps I didn't emphasize this enough:

they don't remember the early days where the Big Three got it right, and they ignore the later days when the Big Three figured it out again.

 

[Lethalchem]

No argument from me. The original poster was considering the days from 1973-1981. I'm saying nothing in that era after about 1970 was worth considering until you get to the much newer engines. Perhaps I didn't emphasize this enough:

AHhh, I see what you're saying. My bad for reading it poorly. Keep in mind that none of the cars (by any maker) were really very impressive (IMHO) during the years you indicated.

 

[1X83Z]

Obviously you've never owned one, if you honstly believe that statement.

Um, has anyone ever owned a 3-liter OHC V8? If you haven't owned a 1994-1996 BMW 530i, then neither have you. If you have no idea what I'm talking about, go back to my post and re-read what I was quoting; it wasn't directed at all V8s, just small OHC V8s (3.0 and 4.0) like Matt C stated.

My point is that there's absolutely no sense in spending loads and loads of money to develop a "small" V8 when a) it has the same power output as a six and b) you've already got sixes in use that do the same job (GM OHV 3.5L V6, GM OHV 3.4L V6, GM OHV 3.8L V6, GM DOHC 3.6L V6 for cars and GM OHV 4.3L V6 and GM DOHC 3.5L 5-cylinder for trucks come to mind, and that's just GM).

And yes, I have owned two domestic V8 vehicles, both GM - currently a '96 Chevrolet Corvette Grand Sport, in fact. Though I really don't like it.

 

[wana b drifter]

can't you get more rpm and better gas milage from a "small" displacement V8 vs. a V6 or I6 with the same displacement.

 

[1X83Z]

Maybe slightly better power across the range, but I'd bet anything fuel economy is worse; I'm considering my own example of BMW's DOHC 3.0L V8 used in the 530i from 1994 to 1996, which got 215bhp but averaged just 20.8mpg (combined EPA city/highway auto and manual) against other 3.0L midsize sedans from the same period - the 1994-1996 Camry V6 used a mostly aluminum 3.0L DOHC V6 that put out just 188bhp but got 24.5mpg (with a 4-speed automatic the sole transmission), and the 1996-1997 Accord V6 used a 2.7L DOHC (non-VTEC) V6 that produced just 170bhp but managed 22.0mpg, also with just an automatic transmission.

 

[///M-Spec]

I disagree with this as well. My 4.6l V8 equates to a tiny 281 cubic inches, yet it puts out 530hp and 560tq. That exceeds many "big block" numbers of the past. I consider myself an American V8 fan, and am very happy with this setup.

Yes, but your Cobra is blown. Any type of supercharging is essentially increasing displacement. What kind of numbers did the old supercharged big blocks make?

Don't get me wrong, though. The Cobra motor is fairly impressive for an emissions legal car at the price point.


M

 

[///M-Spec]

Maybe slightly better power across the range, but I'd bet anything fuel economy is worse; I'm considering my own example of BMW's DOHC 3.0L V8 used in the 530i from 1994 to 1996, which got 215bhp but averaged just 20.8mpg (combined EPA city/highway auto and manual) against other 3.0L midsize sedans from the same period - the 1994-1996 Camry V6 used a mostly aluminum 3.0L DOHC V6 that put out just 188bhp but got 24.5mpg (with a 4-speed automatic the sole transmission), and the 1996-1997 Accord V6 used a 2.7L DOHC (non-VTEC) V6 that produced just 170bhp but managed 22.0mpg, also with just an automatic transmission.

Fuel economy is closely tied to weight. The E34 530i weighed almost 3700lbs; more after options. What do the Camry and Accord from those model years weigh? Several hundred pounds less, I'd wager.

When looking at mileage as an aspect of engine efficiency, make sure you are comparing apples to apples.


M

 

[Lethalchem]

Um, has anyone ever owned a 3-liter OHC V8? If you haven't owned a 1994-1996 BMW 530i, then neither have you. If you have no idea what I'm talking about, go back to my post and re-read what I was quoting; it wasn't directed at all V8s, just small OHC V8s (3.0 and 4.0) like Matt C stated.

My point is that there's absolutely no sense in spending loads and loads of money to develop a "small" V8 when a) it has the same power output as a six and b) you've already got sixes in use that do the same job (GM OHV 3.5L V6, GM OHV 3.4L V6, GM OHV 3.8L V6, GM DOHC 3.6L V6 for cars and GM OHV 4.3L V6 and GM DOHC 3.5L 5-cylinder for trucks come to mind, and that's just GM).

And yes, I have owned two domestic V8 vehicles, both GM - currently a '96 Chevrolet Corvette Grand Sport, in fact. Though I really don't like it.

You're right, I didn't realize you were JUST talking about a 3.0. The comment I took of yours, was in response to a quote about "small V8's", not a 3.0 specifically as I read it. Perhaps it's just a perspective issue, as I consider the old 5.0L made popular in the 1987-1993 mustang engines (302) to be small displacement. They put out 225hp/300tq, and got 27mpg on the freeway.

I don't like the corvette you own either, although I am forced to admit I am impressed that the current model ZO6 can manage 405hp and still get 28mpg. Damn Chevy's.

 

[Lethalchem]

Yes, but your Cobra is blown. Any type of supercharging is essentially increasing displacement. What kind of numbers did the old supercharged big blocks make?

Don't get me wrong, though. The Cobra motor is fairly impressive for an emissions legal car at the price point.


M

I agree with you that the blower increased my displacement to a 393, but your statement was that no true american V8 lover would own a small, efficient V8 engine. I'm saying they would, in this form. You didn't say it had to be naturally aspirated. This is a fairly efficient small displacement engine that simply uses technology to make power. I don't see anyone having too much trouble with that except the old mechanics who refuse to learn how a computer works. At least none of the guys I've taken for a ride seemed to complain.

The big block engines still would not have been efficient with a blower. Gas milage, overheating, the need for forged internals, tuning issues with carbs, all would still be poor. I'd take a blown fuel-injected smallblock that can run in stop and go traffic and get 23mpg over the old bigblocks that overheat at a stopsign and get 8 mpg anyday!

Of course I am forced to admit, I miss the old thump of the big cams. Can't quite get that in my DOHC, but I can still enjoy it in the 5.7l SS Camaro's and C5/ZO6's though.

 

[1X83Z]

Fuel economy is closely tied to weight. The E34 530i weighed almost 3700lbs; more after options. What do the Camry and Accord from those model years weigh? Several hundred pounds less, I'd wager.

When looking at mileage as an aspect of engine efficiency, make sure you are comparing apples to apples.

1995 BMW 530i with a 5-speed automatic transmission weighed 3516lbs; 1995 BMW 530i with a 5-speed manual transmission weighed 3450lbs; 1995 Toyota Camry LE V6 with a 4-speed automatic transmission weighed 3219lbs; 1996 Honda Accord EX V6 sedan with a 4-speed automatic transmission weighed 3274lbs.

Even if you don't consider 297 and 242lbs to be close enough for a true comparison (and keep in mind the Camry got 3.7mpg more than the 530 with both of the 530's transmissions factored in), I'd put the 530i up against the 1996-1999 Duratec Ford Taurus, which had a 200bhp DOHC 3.0L V6, weighed 3327lbs (189 less), had just an automatic transmission, and still beat the 530's EPA rated fuel economy by 2.7mpg (23.5 to 20.8).

I am impressed that the current model ZO6 can manage 405hp and still get 28mpg.

28mpg? In whose gallons? The EPA rating is 18/25, meaning the very most anyone could extract from the vehicle is 25mpg, driving as conservatively as possible, only on the highway. Even if you split your time evenly between the highway and the city, which no-one does, especially in a Corvette, you'd only manage 21.5mpg at the very most. ConsumerGuide split its time evenly city/highway with the Z06 and managed just 19mpg, which is probably the most reasonable number I've stated yet.

 

[Lethalchem]

28mpg? In whose gallons? The EPA rating is 18/25, meaning the very most anyone could extract from the vehicle is 25mpg, driving as conservatively as possible, only on the highway. Even if you split your time evenly between the highway and the city, which no-one does, especially in a Corvette, you'd only manage 21.5mpg at the very most. ConsumerGuide split its time evenly city/highway with the Z06 and managed just 19mpg, which is probably the most reasonable number I've stated yet.

That's because you're quoting paper, and I'm telling you what I've seen in reality. I have three friends with ZO6's. I'm sure you're aware that not all printed information is 100% accurate. Most numbers are the average of what you can expect. The WRX does a little bit better than the window sticker claims as far as gas milage too. Also, if you believe everything you read, my car is supposed to make 390hp/390tq, yet bone stock dyno's are showing 365-380 at the wheels. With just mufflers and an air filter change I put down 417rwhp. I guess Ford just has some REALLY efficient drivetrains.

Not bashing you at all, just saying that it's fairly common knowledge that the C5's get very good MPG for they HP they put out. Mine was about 22 on the freeway before most of my mods.

I belong to a local car club that has a wide spectrum of vehicles in it's ranks. I've really learned a lot about many makes of cars I had never been exposed to before. It has allowed me to have respect for all sorts of automotive creations, because it's showed me what the machinery can do first hand, instead of me simply believing some mag writer or PR guy. It was a real eye opener for me to learn that you can't count on what you read.

 

[///M-Spec]

I agree with you that the blower increased my displacement to a 393, but your statement was that no true american V8 lover would own a small, efficient V8 engine.

Actually, that wasn't me. You have mixed me up with another poster. I was just pointing out that supercharging is same in concept as increasing displacement.


M

 

[///M-Spec]

1995 BMW 530i with a 5-speed automatic transmission weighed 3516lbs; 1995 BMW 530i with a 5-speed manual transmission weighed 3450lbs; 1995 Toyota Camry LE V6 with a 4-speed automatic transmission weighed 3219lbs; 1996 Honda Accord EX V6 sedan with a 4-speed automatic transmission weighed 3274lbs.

Even if you don't consider 297 and 242lbs to be close enough for a true comparison (and keep in mind the Camry got 3.7mpg more than the 530 with both of the 530's transmissions factored in), I'd put the 530i up against the 1996-1999 Duratec Ford Taurus, which had a 200bhp DOHC 3.0L V6, weighed 3327lbs (189 less), had just an automatic transmission, and still beat the 530's EPA rated fuel economy by 2.7mpg (23.5 to 20.8).

I don't. You've proven nothing. The marginally heavier car gets marginally worse gas milage than a marginally lighter car with a similar horsepower. Well duh.

Also, look at gear ratios, aerodynamics and rolling resistance. The 530i wore wider tires.


M

 

[1X83Z]

It was a real eye opener for me to learn that you can't count on what you read.

I don't think you quite understand EPA ratings, so let me inform you. The Environmental Protection Agency rates the cars based on the best fuel economy that they could possibly get in both the city and on the highway. No human being has ever achieved these ratings, and therefore they are the maximum fuel efficiency ratings of vehicles. Without severe modifications, a car would not be able to best the EPA ratings under any circumstances.

I don't. You've proven nothing. The marginally heavier car gets marginally worse gas milage than a marginally lighter car with a similar horsepower. Well duh.

For God's sake!

Fine, 1992-1999 Pontiac Bonneville. First, let me just state how good-looking this thing was. Man, I love that styling - clearly inspired by some sort of airplane (perhaps after a crash landing).

Either way, it was 3446lbs - 4lbs lighter than the 530 manual and 76lbs lighter than the 530iA. And it had just one transmission, a (bad) 4-speed automatic, which achieved a decent 24mpg, hooked to a 205bhp 3.8L OHV V6. So there you have it: the Bonneville weighs nearly the same, has a negligible horsepower difference, has a more outdated, larger engine, and sucks more yest still achieves 3.2mpg more than the 530i.

I'd do gear ratios and tire width but I just don't care that much.

 

[MattC]

Whether you like it or not Pontiac's SD 455 of 73/74 posted 1/4 mile times in the 13s and 0-60 in under 6 seconds as an automatic car. The late 70s W72 400 was a second slower at under 7 seconds but that was still very quick for the day.

 

[///M-Spec]

For God's sake!

Oh, relax. Just listen for a sec.

You stated there is no reason to produce a small V8 when a mid to large V6 can do the same job or better, at least in terms of efficiency. I have no problem with that.

But where I disagree is when you used three different engines in THREE DIFFERENT CARS to prove your point. That's not apples to apples. The 530i weighs considerably more than two of your examples --this increases rolling resistance. The 530i is RWD and your other cars are FWD --the 5 has more powertrain loss. It is safe to assume the 530i had wider tires and is more aggressively geared than the other cars as befitting its more sporting character. The 530i probably had a worse co-efficient of drag, because it was the last of the open-grille and headlight BMWs.

All these things have a direct impact on fuel economy and HAVE NOTHING TO DO WITH THE ENGINE ITSELF. If you really want to make a valid comparision, you need to put all three engines in the same car and measure economy on the same road, same day, etc. etc.

Now, all things being equal, such as displacement and basic architecture, a DOHC V8 has more moving parts and therefore more internal friction than a same sized OHC or OHV V6. (but the V8 also requires less counter balancing compared to a V6) Plus, the 530i likely had more aggressive engine management tuning that geared the motor towards peak power than low speed torque. So in essence, I don't disagree with you. I just have a problem with the method of evidence.


M

 

[Lethalchem]

I don't think you quite understand EPA ratings, so let me inform you. The Environmental Protection Agency rates the cars based on the best fuel economy that they could possibly get in both the city and on the highway. No human being has ever achieved these ratings, and therefore they are the maximum fuel efficiency ratings of vehicles. Without severe modifications, a car would not be able to best the EPA ratings under any circumstances.

Perhaps I don't then, but I can certainly do math, and I know what the three vettes pulled down while on road trips with them to a track. Explain that however you care to. All three were modified, so perhaps that makes a difference, but I've never had too many mods on my cars that made my MPG better.

Anyway, whether a modern V8 can get 28 or 24 isn't really the point of this thread, although it still puts the "old iron" MPG numbers to shame, which DOES have some relevence. My 1993 5.0 V8 had 2.73 gears and ran 1800rpm at 70mph. It consistantly managed 25mpg. My current car, when it just had intake and exhaust mods, comes stock with 3.55 gears and was running 22mpg on the freeway. I think that was respectable for a car over 450hp. I don't know what my mpg is now that I've modded it even more, kinda don't want to find out.