Where's this power coming from??

[iamjeff]

it was my understanding that 1 pound of boost was 1 pound of pressure over normal atmesphereic presure(which changes depending on elevation), but i could be wrong.

pronto said: "Kind of like a bumble bee flying?"

i believe he said this because bees cant fly(at least not according to the laws physics)

didnt gm shut down the turbo buicks because they were faster then their beloved vette?

-jeff

 

[DCVING 6]

The dyno numbers aren't always accurate... with a turbo car that is. If your car downshifts, the turbo is spooled as it comes into 3rd gear. Sometimes it can be very misleading.

 

[equalizer442]

SO... two motors might have identical torque and HP numbers and behave very differently in a car.

a better example then that would be the monte carlo ss and the 442. basically the same car with a few small diferences with totally diffrent engines and the same hp numbers but the ss was about a second quicker.

 

[DCVING 6]

Originally posted by equalizer442
a better example then that would be the monte carlo ss and the 442. basically the same car with a few small diferences with totally diffrent engines and the same hp numbers but the ss was about a second quicker.

they are both slow!

Actually they should be around the same as each other. I had an 86 442, completely bone stock 70k. Raced a buddies 30k mile 87 SS at the track. When you look at different runs where we had similar 60 ft times, we were a tenth or two off of each other. He beat me a couple times, I beat him a couple times.

I raced a couple Monte SS's on the street and only got beat by more than 2 cars once. He had a really quite 383 in it. Let me just say it was really ugly.

 

[Vendor Defendor]

i dont know if any body has ever noticed this, but i think that if you look at a dyno sheet every engine makes the same amount of hp and tq at (i think) 5,262 rpms.. i had an article that explained exactly how this worked, with a mathematical equation and everything, it was someones web site that i found about 6 months ago, because on the same site the guy had an article on GN's, thats how i stumbled upon it.. and looking at dyno sheets it seems to be true.. i dont know if it applied to high reving motors...

and are you serious about us making 450 ft/lbs and almost 300 hp? thats nuts... not doubting you but do you by chance have a copy of the dyno sheet that i can see?

-neil

 

[BM Computer Src]

Yes I have a copy, I'll try to scan it in shortly.

We backed it up with another GN that had a downpipe upgrade, with otherwise same setup as mine. His Dynoed 315RWHP, 460 FT-LBS.

His boost was set at 20 and mine at 16-17 psi. I know thats not totally stock of 15 psi, but my car was the most stock one I knew of at the time. I also locked my converter.

Also the theory of Dyno's not reading turbo car torque #'s correctly is BS. If they are not reading the torque correctly than you MUST throw out the HP #'s as well, because the dyno determines HP by mathmatical figuring of the Torque.

However, the spike can be inaccurate sometimes, as refrenced by the person earlier (like a downshift jerking the dyno around) but to be certain you can see the Torque averaging from the peak to redline and get a good feel. Also you can lockup the torque converter which stops slippage to give a better reading.

Bob

 

[Vendor Defendor]

Originally posted by BM Computer Src
Yes I have a copy, I'll try to scan it in shortly.

cool thanks

-neil

 

[Pronto]

Ya, theoreticly a bumble bee shouldn't be able to fly and a v-6 shouldn't make more torque than a v-8. So much for conventional thinking

 

[V8Killer]

Now if only they could sound as good as a V-8 out the back......oh well, it does have that cool whistle though

 

[The Radius Kid]

Originally posted by V8Killer
Now if only they could sound as good as a V-8 out the back......oh well, it does have that cool whistle though

I don't know about that.A good healthy exhaust can go a long way towards "curing" that problem.

 

[iamjeff]

i dont know, the turbo buick can sound really mean. i definitely dont think it sounds like your average v-6 , maybe hat is because it isnt. and yes, the whistle is the coolest.

-jeff

 

[BUICKTR]

I like that HISSING sound. Most V8 guys know something is up when they hear that sound.

 

[BOOSTD]

Hey, thanks for the interesting information.

I LOVE the sound of these cars; especially when they have no mufflers They don't have the rumble of a V-8 but they dont sound like ricers eather. Definatly a unique "loapy" sound. Add in the turbo screem and you've got a bad A$$ sounding car that will get anyone's attention. You wouldn't believe what sourt of looks I get when people hear that turbo through their window.

This is usually what the V-8rs and the ricers look like...



Got to love these cars

BOOSTD

 

[mgmshar]

A few thoughts...

1. The 231 is an old dinosaur, so it's structurally overdesigned. Cast iron blocks, cast iron heads, heavy pistons with really-thick upper ring lands (newer engines have very thin upper ring lands for emissions reasons), fillet-rolled cranks, etc. A stock 231 can take 20+ psi of boost with no problems. When I tell my LT1/LS1 friends that, they pass-out. How many LS1's have you seen that were modded, and then had broken pistons? It's almost unheard of on Buick's. It's still amazing to me how much spark knock a 231 can take at high boost without breaking a piston. Newer engines with lighter pistons would never tolerate it.
2. It's not peak horsepower, or even peak torque - it's the shape of the torque curve across the RPM band. A modified TR will put 400+ foot-pounds out the crankshaft from 2,000rpm to 5,000rpm. Turbo engines usually have very flat torque curves, which is what you want. Sure, that little Honda may make 200hp at 9,000rpm, but the engine doesn't breathe at all below 8,000rpm - no torque. If you look at a graph of Torque versus RPM, look at the area under the curve in the usuable RPM range - that will tell you how well the engine will pull.
3. As mentioned before, making 400+ foot-pounds with six little cylinders is more efficient than making 400+ foot-pounds with a big-block Chevy. The BBC will be heavier, have more frictional losses, and will have a torque curve that is not as flat as the 231.

Anyway, just some thoughts to add to the discussion...

 

[BOOSTD]

I guess the phrase "they don't make them like they used to" realy applies to these cars. Why does it seem that cars are getting flimsier every year? Is there a reason that engines and even cars in general seem to be less solid? The only three domestic cars that I have seen lately that look like they have some balls are the new supercharged mustang cobra (please, don't hurt me ), the GTP with the supercharger (obviously), and the Dodge Viper. Don't get me wrong, the Camaros and Trans-Ams are cool, but they just don't seem to have the meatyness that the cars of yesteryear had.

Why did the car companies choose to contenue with V-8's (ex. TPI, 5.0, LT1, LS1, LS6) if force inducted V-6's are so much more powerful and efficent? Any ideas?

BOOSTD

 

[mgmshar]

Answers to two of the above questions...

1. Engines get flimsier because engineers have better tools to optimize them. Some simple examples: blocks and heads get lighter because their designs can be "optimized" using finite element analysis, main bearings get smaller in diameter because that reduces friction (and bearing materials have gotten better), and piston ring lands get thinner because that reduces hydrocarbon emissions. Unfortunately, when a design is optimized, it doesn't leave any room for adding more power. Put a turbo blowing 20 psi of boost on an LS1, and it won't take long to hear the "BOOM".
2. V8's are still made and preferred for many reasons, the most important being this: turbocharged engines don't sell in the U.S. Ask Chrysler about that from their 1980's experience. Americans can't stand turbo lag, and they prefer "right now" torque. However, turbo's seem to be making a comeback, at least in the sports compact market (PT Turbo, Neon SRT-4, Supra, etc.)

That enough philosophy for me today...

 

[blackbuick87]

Mike hit the nail on the head. Todays engines can go 200000 miles routinely, but they can not be pushed much beyond the stock specs. Everything is "just big enough" or "just strong enough" to get you up and down the highway and thats it.

The Toyota Supra block is another example of a fine piece of machinery that has been discontinued. One of the strongest bottom ends of all time

 

[Taffy]

Originally posted by blackbuick87
Mike hit the nail on the head. Todays engines can go 200000 miles routinely, but they can not be pushed much beyond the stock specs. Everything is "just big enough" or "just strong enough" to get you up and down the highway and thats it.

The Toyota Supra block is another example of a fine piece of machinery that has been discontinued. One of the strongest bottom ends of all time

The stock block is not discontinued. You can still get new short block 2JZ-GTE (the turbo block) at Toyota. The 2JZ-GT (non-turbo, but quite strong nonetheless) is still put in MANY cars that Toyota sells.

 

[Sinful6]

Good topic(not necessarily tech, but who cares? ).

What makes our Buicks so fast?
Generally the N/A cars lag behind the "turbo crowd" as of late, so the answer to this one would simply be "A turbo."

OK, so what makes our Buicks so fast in comparison to other turbo cars?
Namely, a large(for an OEM turbo application) displacement, engine with a large(again for an OEM application) turbo. Most of the other turbo cars have much smaller displacements, and use the turbo as compensation and then some. This larger displacement(in association with our turboes of course) gives us our amazing torque numbers.I am strongly disagreeing with the misconstrued info that Bob from BM gave us that turbo=torque. There are plenty of turbo cars out there that don't have nearly as high a hp/tq. ratio as our cars. Our advantage over the other turbo cars is had from the displacement. Notice how the 4.1L guys meet/beat our ET's much more easily?

jastrckl brought up a good point about the atmospheres(14.7psi BTW). Although, he did overlook that our engines are not nearly 100% efficient, and combined with the loss of power through compression ratio, the rule of 2atm. ingested = 2x the power is not accurate.

VendorDefendor, The reason that the tq. and hp. numbers intersect at 5252rpm is only because of the formula used in calculating the horsepower.


Just trying to help


-DC

 

[Vendor Defendor]

dont wanna sound too pushy... but did you ever scan that dyno sheet?

thanks...

-neil