I'm really not allowed to say much about the STi as there is a press embargo until May 1st. I will say that the pre-production car was very strong. It would easily spin all four sticky tires in first gear with no more than a 4000rpm launch. It would also chirp the tires again as it shifted into 2nd. I would love to see that kind of power find its way to production. SOA will yell at me if I say any more

gtr-- Our own shop car has over 3000 miles and 900 dyno pulls the break-in since it has been modified in so many ways (EVO 7 cams, HKS cams, adj. cam gears, etc,.) from the start. We'll be testing a fellow forum member's stock EVO (for the 2nd time) on Monday. We'll see if it gained any power from its last dyno test a couple of weeks ago.

Not sure why the big hp discrepency between the EVO and the WRX. The results I've seen from our awd dyno and the awd dynojet at HKS are pretty consistent with each other. I don't like to equate trap speeds with peak hp numbers since there are other influencing factors involved-- especially when comparing WRXs to EVOs-- both of which have very different boost control schemes which don't really come into play on a dyno.

Just my 2c,
shiv

 

I'm just curious as to why you think the Supra was a ringer? What did the magazine test car run? I'm willing to bet I know of Supras bone stock that ran faster or dynoed higher. There's a 15% loss to the wheels on an average Supra. That puts it at 272 whp from factory #'s. My Supra dynoed over 280 rwhp and I've seen others dyno as high as 300 rwhp. Granted that Supra was a freak the majority were on the money or higher. Fastest stock Supra time was a 12.9 @106. Much faster than the 13.6 mags got.

I do believe some ringers are used but I also believe not every car off the lot is the same. Some are stronger or weaker for whatever reason. This just may be one of those cases.

 

No I wouldn't. Not given the swing we have seen between different dynos.

You can't compare the values from two different dynos.

 

Why care about driveline loss? Performance is what matters.

I am certain that there is some way to determine driveline loss. But comparing numbers from two very different dynos isn't the way to do it.

 

I criticize because I see flaws. Should the flaws not be pointed out? Should we all just be dyno yes-men?

 

Remember also that different AWD cars have different drivetrain losses. I suspect that my car would have a higher drivetrain loss than an Evo VIII because my transmission has one extra shaft (and thus an extra gear mesh) in it.

However, as I noted before, if an AWD car really has such a high drivetrain loss, then I would expect to see vastly different trap speeds between a stock FWD Eclipse and an AWD Eclipse. And that simply isn't the case.

 

It would seem like some form of consistent dyno calibration and certification standard would be in order. It is a no win situation for an ordinary joe (or gtr) who wants to provide feedback on their cars performance.

If a person writes about how fast and/or how a car runs stock, or how much better with a new mod everybody says "show us the dyno charts!". When the dyno charts are produced, then there is intense speculation as to the validity of the dyno.

Granted I have seen some dyno charts for stock vehicles that just don't make sense, and are so out of kilter they should be questioned. Overall this is a frustrating excersise to get to the elusive "real" numbers that undoubtedly vary from car to car regardless of the dyno used.

As far as the drivetrain loss it just seems like the most one can hope for is a reasonable average for a specific vehicle type(rwd,fwd,awd) then maybe more specifically to the vehicle itself (EVO vs say a Syclone). I guess if you had a lab environment available, which I am certain is used by the manufacturers, you could do your engine dyno testing then whp testing of a number of cars to achieve a standard rating for drivetrain loss.

I guess in a sense thats what we are really trying to do when we dyno a stock EVO, and then try to bounce it against the manufacturers claim of 271 crank hp. Using various standards for loss we end-up either higher than the 271, or substantially lower.

This just seems to escalate the controversy of whether the dynos are wrong, the loss factor is incorrect, or the manufacturer is innaccurately listing the cars hp/tq numbers.

Performance testing at the track will help confirm what a car is really making, but there are also variables of track, location, weather, and driver skill that will leave many questions as well.

Personally I would like to see 3-4 major tuner shops collaborating to figure out how to create a more definitive methodology for dyno calibration and testing. I realize that each tuner is in business to build their own client base and provide parts and services in competition with the other tuners. It just seems like some basic rules of engagement before slugging it out might make everyones lives a little better. Instead I see a lot of controversy and back-biting as to who is doing things right and what equipment is right.

This is just an observation, and I do know that some tuners do talk amongst themselves from time to time. If I am wrong about what I have said I apologize, and stand ready for correction.

 

The Supra that was a ringer was obviously the one Car and Driver had for the March 1993 test. That car made more power and had cheater rubber on it for that review. No other Supra tested for the magazines went as fast, and even Car and Driver commented later that the car was "pre-production" and that the test results were skewed.

Car and Driver March 1993 Test

0-60Mph 4.6 sec
0-100Mph 11.1 sec
0-130Mph 19.8 sec
0-150Mph 29.6 sec
1/4 Mile 13.1 @ 109Mph

Car and Driver September 1993 Test

0-60Mph 5.2 sec
0-100Mph 12.3 sec
0-130Mph 22.5 sec
1/4 Mile 13.8 sec @ 106Mph

Quote" The prototype we tested in March demonstrated even more straight-line speed, but we put our faith in these production-car numbers"

That would be a "ringer" pre-production car as tested by the same magazine who admits the March test was not indicitive of the production Supra's times.

Brett.

 

Ok, I've gained 25lb to my belly during the college years so i weight close to 250 LB.

Guess whay. My best trap speed is 101.77. I also have a sunroof 3398+250Lb and over 1/2 tank of gas. I think i'm over 271hp. I'll post my slips.

 

shiv,

How about comparing trap speeds with the same car to determine which is more powerful? If you get a chance would you let us know the trap speed of your evo with 188 Wheel horsepower?

Yes, the evo has lots of area under the curve and etc but, i'm curious if my car is more powerful than your and why? I think we all want to know if SCC's evo is really a ringer or perhaps not?

 

gtr, Using your trap speeds I come up with about 290hp. Not exactly sure on your total weight though, so I used 3515. Do you know your total weight?

 

Opps had a typo. That'll be 3298+250=3548. What I was thinking was defintily underrated flywheel hp.