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#41 · (Edited)
What dont you get? The Earth is round is a fact. The ocean makes up 71% of the Earth surface is a fact. Sickle cell anemia confers resistance against malaria in certain part of Africa is also a fact.

And as a great example, consider champ cars if you would.

These cars are making little more than 1000hp in a small displacement engine. BUT there is a catch.

They are running on methanol (again my point stands about fuel management and the prevention of detonation).

Their engine produce and enormous amount of heat (typical when combining small engine with high compression).

They can rev super high (9000+ rpm), because they have very high compression ratio.

They are turbocharged.

Your saying that it's not possible to make alot of power by upping the boost on a high compression engine is incorrect. It CAN be done.

The weak side is that it's not really streetable, however you deny it, it can and HAS been done.
 
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#42 ·
Darkstang said:
Stock Supra run mid to high 13s. Supra are extremely hard to launch because of there hp/torque curve. But once they get moving they pretty fast. Did you race full qtr mile???
Click to expand...

Actually, MT tested 98 Supra TT and it ran 13.1

AWD owns everything from a stop. Put 12 second awd vs BPU supra on 60mph roll on, then you hate your awd!
 
#43 ·
EclipseXstacy said:

And as a great example, consider champ cars if you would.

These cars are making little more than 1000hp in a small displacement engine. BUT there is a catch.

They are running on methanol (again my point stands about fuel management and the prevention of detonation).
Click to expand...
Sigh, I've quoted a very reputable magazine, summarized basic physics, and even tried to give examples.
Champ Cars run very high boost...40psi+. Now why wouldn't they just run something ridicules like 20-1 compression with less boost? Because they make more power with 13-1 and more boost.
And I wouldn't call on methanol to be your example of 'fuel management'. Only a small select few run methanol of the street...and they are pushing the envelope of 'streetable'.



They can rev super high (9000+ rpm), because they have very high compression ratio.
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Lol, they rev super high, because of a myriad of things...not just because of high CR. And most champ cars rev over 12000rpm.


They are turbocharged.
Click to expand...
Some are, I believe Indy rules don't allow forced induction.


Your saying that it's not possible to make a lot of power by upping the boost on a high compression engine is incorrect. It CAN be done.
Click to expand...
I _never_ said that. I said that all things being equal, you can make more power (realistically) with a lower CR and more boost then one with a higher CR and less boost.


The weak side is that it's not really streetable, however you deny it, it can and HAS been done.
Click to expand...
Why are you putting words into my mouth...where did I ever 'deny' that you couldn't boost high CR engines?


Rogue
 
#44 ·
like I said, it's possible.

And the barely streetable part is running on methanol.
 
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#45 ·
Some are, I believe Indy rules don't allow forced induction.
Click to expand...
Actually virtually all champ cars run on turbocharged application.



I _never_ said that. I said that all things being equal, you can make more power (realistically) with a lower CR and more boost then one with a higher CR and less boost.
Click to expand...
If you are talking on the street, then yes a lower compression engine is better suited in terms of reliability.
 
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#46 ·
Rogue_Ant said:
Have you actually worked on an LS1 F-Body?
It is actually quite packed, you might be able to make a smaller front bumper, but then it isn't going to be as aerodynamic. A quarter of the engine already sits under the windshield.

Rogue
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It's not as bad as people make it out to be... relatively 1% of anything servicable is under that cowl. So far I have had the car down to the block to replace head gaskets and removed my OptiSpark (which requires removing the waterpump.) Changed plugs several times and I don't find it to be too difficult at all. :p Its all you people with big hands that seem to have all the issues. Besides when the going gets really tough it takes a really short amount of time to just drop the motor out the bottom :D
 
#48 ·
EclipseXstacy said:


Actually virtually all champ cars run on turbocharged application.
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Wrong. Like I said earlier, Indy cars are N/A. Here is a quote from Indy's web page:

Engine Regulations


Type: 3.5-liter V8, 32-valve dual-overhead cam (DOHC), Normally aspirated
no turbocharger)
Size: 3.5-liter displacement, 213.580 cubic inches
Max. bore diameter 93 millimeters
Four camshafts, four valves per cylinder
Weight: Minimum weight is 315 pounds. Dry weight - no headers, clutch, ECU, spark box or filters
RPM: 10,700 maximum (incorporates a rev limiter)
Power: Estimated 650 horsepower
Fuel: Methanol
Injectors: Electronic
Cost: $95,000
Models: Chevy Indy V8
Infiniti Indy
Manufacturers: Chevrolet Division, General Motors Corporation
Infiniti Division, Nissan North America, Inc.

Check it out at http://www.indyracing.com/cars/engine.php if you don't believe me.

EclipseXstacy said:

If you are talking on the street, then yes a lower compression engine is better suited in terms of reliability.
Click to expand...
I am talking in terms of max potential power.

Let me see if I can explain this so everyone will understand.

At the pistons highest point (TDC) there is a small volume of compressed fuel/air (compression stroke).
Now for an engine that has 11-1 CR, for sake of argument, lets say there is 10mm of distance between the piston and the head.
Now the formula for volume of a cylinder is:

V=pi*r^2*h

So imputing what we know (4g63 specs) the given volume for 10mm would be 3.46CI.
Now an engine with a lower CR might have 20mm of distance too the head. Now if input these #s then we get a volume of 6.9Ci.

What does all this mean?

Well since the lower CR engine has more volume to fill, then you can force more air/fuel into a larger volume then a smaller one.
And once again...more air/fuel more power.

Rogue
 
#49 ·
Rogue_Ant said:


Wrong. Like I said earlier, Indy cars are N/A.
Click to expand...
notice i did not imply all. but you are wrong on your part to state that all champ cars are N/A. Actually, 3.5 Liter is quite a bit of displacement for champ cars, the one Mercerdes made (which is turboed by the way) is about 2.5 Liters.

I am talking in terms of max potential power.
Click to expand...
Wrong again. Because higher compression ratio allows you to force in more air with less aid from the turbo, you can still make gobs of power from lesser boost.

Both systems can work. One is more expensive on the part of the driver, requires very combustible kind of fuel (methanol), and the risk of detonation is higher, but done RIGHT, it can produce just as much power as a lower compression engine on higher boost.

The volume may be Little, but the air is already compressed. Is comparable to a double volume, half compressed.
Click to expand...
 
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#51 ·
"For road-course competition, the rules mandate a minimum weight of 1550 pounds, 40 in. of turbo boost (5.4 psi)
, an overall length between 190 and 196 in., an overall width of 78.5 in., and a maximum body width of 63 in. And the car can't be higher than 32 in."

courtesy Popularmechanic, titled CART vs IRL.
 
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#52 ·
oh man it seems to me that youve just been
Image


peace (sorry if i caused some people to be pissed but it was a perfect opportunity and i had to take it :D )
 
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#54 · (Edited)
EclipseXstacy said:


notice i did not imply all. but you are wrong on your part to state that all champ cars are N/A. Actually, 3.5 Liter is quite a bit of displacement for champ cars, the one Mercerdes made (which is turboed by the way) is about 2.5 Liters.
Click to expand...
Tell me exactly when did I say all Champ cars are N/A??? Considering I never said this, why are you (again) putting words in my mouth?
I said that I didn't think Indy cars (IRL) were turbo'ed, which I was correct.


Wrong again. Because higher compression ratio allows you to force in more air with less aid from the turbo, you can still make gobs of power from lesser boost.
Click to expand...
LOL please explain why higher compression allows you to 'force in more air' into the cylinder? :rolleyes:
The only thing that 'forces' air into the cylinder is a turbo/supercharger (and inertial supercharging).
SO exactly how does a high CR ram more air/fuel into a cylinder?!?


Both systems can work. One is more expensive on the part of the driver, requires very combustible kind of fuel (methanol), and the risk of detonation is higher, but done RIGHT, it can produce just as much power as a lower compression engine on higher boost.
Click to expand...
Actually Methanol is _LESS_ combustible then regular Gasonline....this is why it is less likely to detonate under high boost situations.


The volume may be Little, but the air is already compressed. Is comparable to a double volume, half compressed.
Click to expand...
Tell me then, can you physically ram (compress) more air into a 2liter container or a 1liter? Obviously basic physics dictates you can have more in the larger container.
If you don't understand this very basic concept then go take a high-school level physics class and take notes.

Rogue
Click to expand...
 
#55 ·
Ok, I'm going through the whole front page and I'm like wtf! Nobody has mentioned that there is a NON TURBO Supra ? Because if you won on a stock turbo that's probably a N/T Supra, it pulls out 220hp and your dsm with more boost can put out just a little more than that. So that's my opinion, it was a n/t supra.

As for the guy who sold his GS-T to get an AWD, I'd tell him to get a dual stage boost controller so he won't have as much problem launching as he thinks... I guess yea awd launch is cool, but what about a rolling start ? :)
 
#56 ·
EclipseXstacy said:
"For road-course competition, the rules mandate a minimum weight of 1550 pounds, 40 in. of turbo boost (5.4 psi)
, an overall length between 190 and 196 in., an overall width of 78.5 in., and a maximum body width of 63 in. And the car can't be higher than 32 in."

courtesy Popularmechanic, titled CART vs IRL.
Click to expand...
Once again.. Go to the damn link I posted. IRL doesn't allow turbos. Your quote has no relevince since it is obvously saying that CART allows Forced induction, and Indy doesn't. Your just proving my point that not all champ cars are turbo'ed.

Rogue
 
#57 ·
That website has some basis to it. After all, it is linked to DSMtalk. :rolleyes: And yes, I did look at the INDY racing website. And so was the CART website.

I am not putting words in your mouth. If that is what you think then you are the one missing the point. So, ok Champ cars can either be N/A or turbocharged.

The N/A 3.5 L Chevy V8 does everything the 2.5 L does, but without a turbo. And it makes 650hp as opposed to the 900+ hp produced by the smaller displacement turbo engine.

If you actually read the history of Champ cars. First there was CART, the world racing organization you could say. Then IRL splits off, and become an organization all by itself (the "domestic" version). They just do oval racings.

And here is another thing. Cart used to allow turbocharging back in the early 90s and the engines back then were capable of 14,000+ rpm, making immense amount of hp. Nowaday, if I am correct CART banned it.

BUT, Indy racing DOES allow turbocharging but only at a certain PSI. The point is not what organization still allows the use of turbocharge, the point is that you can make BIG power from little revvy engine!! What dont you understand??

Oh oh you want me to show you how. Ok, for the sake of simplicity, lets say the DSM engine can only rev to 7000 rpm and the compression ratio is 7.5. The champ car has double the ratio (15:0). And lets say that the clearance between the the piston and head for the 4g63 engine is 20mm like you said and that for the champ engine is 10 mm.

Considering that both are at max rpm, this means that for every one TDC that the 4g63 makes @ 7k rpm, the champ car will make 2 TDC @ 14k rpm.

Simple math. 20 mm clearance of air for the 4g63 per period versus 10mm + 10 mm clearance of air for the champ engine per period of time. This shows that the champ engine forces air in at twice the speed, so in essence, the available air is the same PER period! But since higher compression champ piston is moving at double speed, it forces air in more powerful than the lower compression 4g63 engine, thus the need for lower boost!

Do you frikking get the concept????? If you dont then I give up because I am talking to a blind person.
zzzz
 
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#58 ·
man i forgot what the hole argument was about, LET IT GO zzzz zzzz zzzz zzzz

peace
 
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#59 ·
EclipseXstacy said:
That website has some basis to it. After all, it is linked to DSMtalk. :rolleyes: And yes, I did look at the INDY racing website. And so was the CART website.

I am not putting words in your mouth. If that is what you think then you are the one missing the point. So, ok Champ cars can either be N/A or turbocharged.

The N/A 3.5 L Chevy V8 does everything the 2.5 L does, but without a turbo. And it makes 650hp as opposed to the 900+ hp produced by the smaller displacement turbo engine.

If you actually read the history of Champ cars. First there was CART, the world racing organization you could say. Then IRL splits off, and become an organization all by itself (the "domestic" version). They just do oval racings.

And here is another thing. Cart used to allow turbocharging back in the early 90s and the engines back then were capable of 14,000+ rpm, making immense amount of hp. Nowaday, if I am correct CART banned it.

BUT, Indy racing DOES allow turbocharging but only at a certain PSI. The point is not what organization still allows the use of turbocharge, the point is that you can make BIG power from little revvy engine!! What dont you understand??
Click to expand...
Christ, you forgot the whole arguement. The arguement was about lower static CR with higher boost to a higher CR engine with lower boost. The arguement wasn't about Champ cars at all.


Oh oh you want me to show you how. Ok, for the sake of simplicity, lets say the DSM engine can only rev to 7000 rpm and the compression ratio is 7.5. The champ car has double the ratio (15:0). And lets say that the clearance between the the piston and head for the 4g63 engine is 20mm like you said and that for the champ engine is 10 mm.

Considering that both are at max rpm, this means that for every one TDC that the 4g63 makes @ 7k rpm, the champ car will make 2 TDC @ 14k rpm.

Simple math. 20 mm clearance of air for the 4g63 per period versus 10mm + 10 mm clearance of air for the champ engine per period of time. This shows that the champ engine forces air in at twice the speed, so in essence, the available air is the same PER period! But since higher compression champ piston is moving at double speed, it forces air in more powerful than the lower compression 4g63 engine, thus the need for lower boost!
Click to expand...
If you don't understand that CR has nothing to do with ramming more air into the cylinder, then you need to learn more about engines. The only thing a higher CR does is compress the air/fuel mixture IN the cylinder.
Your whole 'point' with the champ car engine is null and void. The higher revving engine doesn't 'ram' more air in because the higher CR it _injests_ more air because it is revolving at a much faster speed.

Why don't you look at the most powerful engines in the world?
Try Top-Fuel dragsters. They don't run super high CR and low boost. They run ridiculasly high boost and lower CR.
They have the money, they have the resources, they run what makes the most power.


Rogue
 
#60 ·
LOL, actually compression ratio has partial effect on the speed/rate of air intake. Ever notice why tuners replacing their stock cams with aggressive cams into their V8 engines. Yes, so they can get higher compression ratio, which means more air is forced into the engine, and more power is made. Now, Another reason that a champ car can rev very high is due to having very light rods and pistons.

And yes, champ cars fit perfectly in this argument as you flatly stated higher compression engines and lower boost can't make alot of power and I have contradicted you. :rolleyes:

If you find it so important to keep arguing, then that is f*cking fine with me. After all, blind people don't think, just blabber.
 
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