STi vs new vette

[YBNormal07]

Just a couple of explanations. Case you hadnt thought of them.

Appreciate it!!

[TSi AWD]

Seriously...do you know what PSIA stands for? As in "absolute"? As in the pressure used within your manifold to manage boost? Might want to read up on the effects of altitude here. Not trying to ping on ya or anything, but two car's with the same setup will NOT hit the same boost pressure at different altitudes. It all has to do with your AFR's. Less absolute pressure to start with means you will have to target a higher boost to get the same performance level, which means different maps all together

Turbo cars simply do not suffer as badly as compaired to NA and superchargers. Even if you have it set to 15PSI, the turbo may have to spin what is normally 20PSI to pump it in. But then you have more heat and less 02 but it is NOT as bad as One may think but certainly a factor. I know there is less 02 and certainly slower spoolup and faster heat soak. You set a wastgate to 15PSI, at sea level and at 5380feet you will get 15PSI albeit with less 02. All other cars will be less, I know Colorado is the land of the 13 second Z06 .

[scooby24]

Turbo cars simply do not suffer as badly as compaired to NA and superchargers. Even if you have it set to 15PSI, the turbo may have to spin what is normally 20PSI to pump it in. But then you have more heat and less 02 but it is NOT as bad as One may think but certainly a factor. I know there is less 02 and certainly slower spoolup and faster heat soak. You set a wastgate to 15PSI, at sea level and at 5380feet you will get 15PSI albeit with less 02. All other cars will be less, I know Colorado is the land of the 13 second Z06 .

Explain then why every STi here in KC I've talked to (5) all cannot push more than 12.5 psi to redline? Even though on my Utec I have my boost number maxed out when others run about 14.5 psi?

STi's I've talked to 2 were cobb, me utec, another utec, and the fifth is running a MBC. None of us can push more than 12.5 psi at redline.

[Dan00Hawk]

Internet Message Board Debate Rule #57:
If you're proven wrong about one particular topic (drivetrain loss, for example), then you should switch topics midstream to reclaim your perceived position of authority. Repeat as often as necessary at the risk of hijacking every thread you participate in.

[TSi AWD]

1of 2 reasons.

Sti's have TINY TINY Turbos and fall off to begin with. I mean I have no Idea why SOA decided to use such a small turbo to begin with on a motor that large. 16G atleast. Butr thems the breaks for haveing a F4 configuration which makes exhaust manifolds LONG and LAGGY.


ALSO it is a wastegate issue and probably a very loose spring from the factory. Tighten it up. Weld it shut I bet you hit 30


proven wrong about DRIVETRAIN LOSS?? please, go run that Sti and tell me what it traps at 400 crank horse power sorry, you guys are dreaming. If he truely does, then he will trap at 113-114MPH, I doubt he will break ten.

[scooby24]

proven wrong about DRIVETRAIN LOSS?? please, go run that Sti and tell me what it traps at 400 crank horse power sorry, you guys are dreaming. If he truely does, then he will trap at 113-114MPH, I doubt he will break ten.

I think the point is that if drivetrain loss is truley a percentage, like what has been commonly accepted in the automotive community then it does not matter what crank hp you are putting down but rather your whp will determine your trap speed.


This explains why a 300 chp RWD car will out trap a 300 chp AWD car.

Therefore a 400 chp STi is going to trap lower than a 400 chp RWD car. Also I'm guessing you are basing your guestimates based on your Car. keep in mind an EVO has been shown to have less drivetrain loss than a Subaru. Also remember we are shifting one more time than you guys. 5 gears to go through instead of just 4.

If the STi had longer gearing I'd guarantee we'd be trapping much higher.

[TSi AWD]

As long as you can shift fast enough I see Scoobys trap at 188-120's with the respective WHP on FP Greens. STock turbo ones about 108-109 at best I have seen. I still doubt that STI has 400 Crank HP and too many variables to have a simple strick percentage loss.

Car. keep in mind an EVO has been shown to have less drivetrain loss than a Subaru

Not really they just make more power easier and are more peaky in the top end as opposed to dieing off (STOCK TURBO). And yes having 5 long gears owns as far as roll racing and 1/4 is concerned.

[scooby24]

Not really they just make more power easier and are more peaky in the top end as opposed to dieing off (STOCK TURBO). And yes having 5 long gears owns as far as roll racing and 1/4 is concerned.

What do EVO's put down stock? I heard around 230 to 240.

Guess what STi's put down stock? 230 to 240.


Where did that extra 25 crank horsepower go that STi's have over the EVO's?


What do stock EVO's (with a good clutch) run at the track? Mid to low 13s.

What do stock STi's run at the track? Mid to low 13s. With the exception of YB's car. He got a factory freak or is the best driver evar.

[Dan00Hawk]

You can't win an argument with someone who knows (or thinks) they are right...

If drivetrain loss is not a constant percentage when HP increases, then please explain where my previous post in this thread with the calculations and linked dyno examples between an RS and a WRX is flawed. http://www.clubwrx.net/forums/showpo...9&postcount=60

That's as close as we're going to get without putting two different motors on an engine dyno, then dropping them in an STi, and then doing a regular chassis dyno. And I don't expect any of us to do that anytime soon.

All you've offered is opinion and speculation. I gave credible examples along with factual and nearly scientific proof. Drivetrain loss IS a fixed percentage as HP increases. Prove it to me otherwise if you'd like (or think you can...).

[TSi AWD]

What do EVO's put down stock? I heard around 230 to 240.

Guess what STi's put down stock? 230 to 240.

Not by my experience. At my local DynoJet my Evo put down 232 WHP. The STi's read at 250's, lowest I saw was 246. They are faster then me too so it makes sense.

What do stock EVO's (with a good clutch) run at the track? Mid to low 13s.

What do stock STi's run at the track? Mid to low 13s.

RIGHT with the Evo's numbers they trap at best at 103MPH. I have seen anywhere from a 15 flat for a STI all the way to a 12.8 @ 106. Again STi's have the advantage stock. People just need to know when to shift them, from MY understanding it is right at 6000 and then bang it through stock or near stock.

If drive train loss is not a constant percentage when HP increases, then please explain where my previous post in this thread with the calculations and linked dyno examples between an RS and a WRX is flawed. http://www.clubwrx.net/forums/showp...09&postcount=60

No one has been able to fully realize the power loss due to a tranny. Only TRUE way is to dyno the motor then dyno it with a tranny. Also running a car and its TRAP are a huge indicator. I merely suggest a 1/4 mile run then I GET HIT with excuses why the STi traps lower A Trap is a TRUE sign of WHP, we Know the WHP, so we can assume crank.

Drivetrain loss IS a fixed percentage as HP increases. Prove it to me otherwise if you'd like (or think you can...).

Nope, my proof is when that "400CHP STI" traps at 109MPH. If it hits 113MPH well then maybe you have something here. I am also a lil worried about all these other excuses for a lower trap. With so many inconsistencies we may never know. It is not a STATIC loss everyone thinks it may be there is a curve especially as the power increases. BUT stock you are probably correct with the 20% or so.


300 Crank advertised. MY DYNO showed 256WHP, less then 20% from MY experience. Using a Mustang Dyno you will get lower numbers, remember a dyno really only shows improvements or losses and is only relative to the other cars that dyno on it.

Mustang Dyno Evo = 200WHP car.

[Dan00Hawk]

No one has been able to fully realize the power loss due to a tranny. Only TRUE way is to dyno the motor then dyno it with a tranny. Also running a car and its TRAP are a huge indicator. I merely suggest a 1/4 mile run then I GET HIT with excuses why the STi traps lower A Trap is a TRUE sign of WHP, we Know the WHP, so we can assume crank.

For the RS and WRX, we HAVE the motor dyno numbers from Subaru. We HAVE the same whp dyno numbers from the same dyno machine. How much more consistent can it get? Did you even LOOK at my post??? Why would you assume crank when we have it straight from Subaru? Both cars with the same driveline and different motors had the SAME percentage drivetrain loss. Trapspeeds vary with weather conditions and too many driver variables. A dyno is SAE corrected and will be consistent, and is much more reliable for the purposes we are discussion here (drivetrain loss). My examples were even done on the same dyno at the same shop...

Nope, my proof is when that "400CHP STI" traps at 109MPH. If it hits 113MPH well then maybe you have something here. I am also a lil worried about all these other excuses for a lower trap. With so many inconsistencies we may never know. It is not a STATIC loss everyone thinks it may be there is a curve especially as the power increases. BUT stock you are probably correct with the 20% or so.

I don't know why you are so hung up on what someone is ESTIMATING their crank HP to be on an STi. As I said, without pulling the modded motor and throwing it on an engine dyno, you won't know. All you have to go by is the whp and estimated drivetrain loss expressed as a percentage, which I've already shown to be consistent as HP increases. Why do I feel like I have to keep repeating myself to get this to sink in for you?

300 Crank advertised. MY DYNO showed 256WHP, less then 20% from MY experience. Using a Mustang Dyno you will get lower numbers, remember a dyno really only shows improvements or losses and is only relative to the other cars that dyno on it.


Mustang Dyno Evo = 200WHP car.

Please show me a situation where crank HP and wheel HP stay at a constant loss (50 hp, for example), and not at a fixed percentage as HP increases. I've done the work to show you that two cars with identical drivelines and different motors/hp will lose the same percentage through the driveline, yet you still don't seem capable of understanding it. Were your math teachers this frustrated with you too?

[TSi AWD]

the RS and WRX, we HAVE the motor dyno numbers from Subaru. We HAVE the same whp dyno numbers from the same dyno machine. How much more consistent can it get? Did you even LOOK at my post??? Why would you assume crank when we have it straight from Subaru? Both cars with the same driveline and different motors had the SAME percentage drivetrain loss. Trapspeeds vary with weather conditions and too many driver variables. A dyno is SAE corrected and will be consistent, and is much more reliable for the purposes we are discussion here (drivetrain loss). My examples were even done on the same dyno at the same shop...

WHOA slow your roll there tiger I know that you are excited but let's calm down

Which dyno machine? My dyno says LESS then 20% whp loss, yours says different, didn't I say that a DYNO is not a reliable to gauge absolute whp? Crank numbers have been skewed before, Mazda, Chevy, Mitsu, why not the Scooby? I like how you try to WRITE OFF the trap explanation, sorry, it stands as an EXTREMELY accurate way to gauge WHP, sorry.


My numbers? STI 256 WHP=15% or so, guess the dyno is wrong? or maybe it has 310 crank hp, idk.

I don't know why you are so hung up on what someone is ESTIMATING their crank HP to be on an STi.

Because they are.... He said crank hp=400 I called against it, prove it. That car will run certain times to have 400CRANK HP despite any perversion of the truth.

All you have to go by is the whp and estimated drivetrain loss expressed as a percentage, which I've already shown to be consistent as HP increases

Not that simple,. Sorry. It is the EASIEST WAY TO ASUME which is what you are doing. it is not 100% accurate it gets skewed as you add and take whp but stock there is a constant I guess you working on show cars makes me wrong huh?



I am sorry I am aggravating you, but here is a SIMPLE way to prove me wrong, run that STI, run it, 109Trap=400hp, no way.

[scooby24]

I am sorry I am aggravating you, but here is a SIMPLE way to prove me wrong, run that STI, run it, 109Trap=400hp, no way.

Your whole arguement here is flawed. Trap has absolutely 100% completely NOTHING to do with crank hp. You could have 1 thousand crank hp but if you have 98% drivetrain loss you aren't going to run for anything.

That arguement just does not work man.

[TSi AWD]

Your whole arguement here is flawed. Trap has absolutely 100% completely NOTHING to do with crank hp.

Yes, wheel WHP does, bu we KNOW WHP, and someone is assuming 400 CRANK

I said it has less Crank HP and it probably does, like I said before my magical Dynojet magicaly read a 15% loss, a full 5%. Trap does ALOT to indicate the cars WHP and CRANK. Look at a Vette, 350 Crank, 108 trap on the MONEY. 400HP? trap at 114? some people may get an IDEA of the trap based on crnak HP, if you havew 400, in a STI it better break 110MPH, run the car, a trap will tell.

You could have 1 thousand crank hp but if you have 98% drivetrain loss you aren't going to run for anything.

Nobody is dumb enough to assume that, I see the point you are trying to make and it is a lil weak.

[Dan00Hawk]

WHOA slow your roll there tiger I know that you are excited but let's calm down

Sorry, didn't realize I was going too fast for you. Sounds like it's a common occurrence, though...

Which dyno machine?

The one at Cobb, that I provided the link to. Again, you apparently haven't bothered to read.

My dyno says LESS then 20% whp loss, yours says different,

I compared an RS to a WRX. They have different drivetrains than an STi. Again, if you had bothered to read anything, you would realize that. I chose the RS and WRX because they have the same drivetrain, but different motors. There's no easy way to do that with an STi because we don't have two separate examples with crank HP under the same drivetrain. I would fully expect an STi to have different percentage loss than a WRX, as it has a different driveline. Capiche?

didn't I say that a DYNO is not a reliable to gauge absolute whp?

Actually, you said: "remember a dyno really only shows improvements or losses and is only relative to the other cars that dyno on it." So I used the same dyno in my example. Hence, it should be credible according to your own standards.

Crank numbers have been skewed before, Mazda, Chevy, Mitsu, why not the Scooby?

We don't have anything else to go on unless you're volunteering to pull motors and put them on an engine dyno. And if Subaru is skewing them, they would at least likely be consistent between the RS and the WRX. You're really reaching here...

I like how you try to WRITE OFF the trap explanation, sorry, it stands as an EXTREMELY accurate way to gauge WHP, sorry.

But it does NOTHING to show drivetrain loss from crank to whp. You're merely being evasive to the topic. I agree that an increase in trap speed will correlate to an increase in whp. But tell me how you then estimate what the crank hp is from that? You can't, and you haven't...

My numbers? STI 256 WHP=15% or so, guess the dyno is wrong? or maybe it has 310 crank hp, idk.

Okay, so you are losing 14.6% through the drivetrain. When you dyno 341 at the wheels, then you'll be at 400 crank, assuming you make no changes to the driveline components. That's my point...

Because they are.... He said crank hp=400 I called against it, prove it. That car will run certain times to have 400CRANK HP despite any perversion of the truth.

I don't really care what someone claims their crank HP to be. If that's your mission to disprove it, fine. But you have to go about it the correct way. And your method is incorrect.

Not that simple,. Sorry. It is the EASIEST WAY TO ASUME which is what you are doing. it is not 100% accurate it gets skewed as you add and take whp but stock there is a constant I guess you working on show cars makes me wrong huh?

You totally misread what I was saying, which is beginning to be a common theme for you here... What am I assuming? Show me where my math was wrong, or the examples I gave are wrong... Where do you get show cars from?

I am sorry I am aggravating you, but here is a SIMPLE way to prove me wrong, run that STI, run it, 109Trap=400hp, no way.

My Firehawk has dynoed between 401 and 406 rwhp on 3 separate occassions (twice on SpeedInc's dyno, and once at FLP's dyno). My trap speeds have ranged from 111 - 115 mph depending on weather conditions (warm humid and low barometric pressure vs cool dry and high pressure). Which method (track or chassis dyno) appears to give more consistent results? That's a 40 hp difference according to my trap speeds, yet the dyno shows consistent readings within a 5 rwhp range. Yet you want to stand by trap speeds alone as the most accurate measuring tool...

I also have yet to see you give a formula or calculation of how trap speed will allow you to determine crank hp. At least either prove me wrong in my example, or do something to prove yourself correct. Again, so far it's only been speculation and opinion on your part.

Cheers!