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Your dyno predictions

Posted: Fri May 14, 2004 1:15 am
by mTk
I'll be dynoing this saturday afternoon, curious what numbers you guys think i will put down. I'll buy a cookie for whoever is closest :)

-'93' Sport sedan 5mt
-legazee intake, cone filter
-MSD ignition/magnecor plug wires/ngk coppers
-3" bellmouth turbo-back exhaust (catless, straight through melon shooter)
-~10 psi boost


MK

Posted: Fri May 14, 2004 1:21 am
by THAWA
160hp
170lb/ft

just stabin in the dark there :)

Posted: Fri May 14, 2004 1:22 am
by legacy92ej22t
Hmmm....I'm gonna say 145 whp and 165 ft. lbs..

Posted: Fri May 14, 2004 1:24 am
by legacy92ej22t
You beat me to the punch AGAIN! :)

Posted: Fri May 14, 2004 1:33 am
by THAWA
too slow joe :)

Posted: Fri May 14, 2004 3:54 am
by Brat4by4
Not knowing the setup of your exhaust (cats? muffler?)....

I'll say 150 whp 165 wtq.

Posted: Fri May 14, 2004 5:18 am
by mTk
updated exhaust specs.

MK

Posted: Fri May 14, 2004 5:49 am
by FG!!
135 peak hp

Posted: Fri May 14, 2004 2:41 pm
by Brat4by4
it had better be a nice cookie, too!

Posted: Fri May 14, 2004 5:41 pm
by QuickDrive
With the fact our cars are AWD I'd almost rather see a CHP Dyno number just to feel better, than a WHP since it'll be way lower than you'd like.

Just rambling...

Posted: Fri May 14, 2004 8:35 pm
by BAC5.2
155whp, 170wtq.

Just shy of what the WRX puts down.

Posted: Sun May 16, 2004 8:10 am
by mTk
Guys all guessed high :) Max psi turned out to be 9.3. Looks like FG gets the cookie :P

MK

Posted: Sun May 16, 2004 3:15 pm
by legacy92ej22t
mTk wrote:Guys all guessed high :) Max psi turned out to be 9.3. Looks like FG gets the cookie :P

MK
Absolutely unacceptable! I want numbers! :P

Posted: Sun May 16, 2004 7:58 pm
by BAC5.2
135hp at the wheels? Damn, seems low :(

Posted: Sun May 16, 2004 8:13 pm
by vrg3
That number is meaningless unless you put it next to other numbers from other AWD cars on the same dynamometer, though, right? Cuz they all have different internal friction and the friction between the rollers and the tires can vary too...

I remember the AWD dyno Sport Compact Car put their second Project Impreza on gave them a number like 90 hp stock.

Posted: Sun May 16, 2004 10:07 pm
by evolutionmovement
If using a dyno for anything than tuning, I think the only decent numbers are ones calculated from a drag run and a weigh in. I personally just want my car to be fast enough to be fun whatever those numbers are. There are too many variables to really try to get hard numbers to quote.

Steve

Posted: Sun May 16, 2004 10:32 pm
by BAC5.2
Nah, friction between the rollers and the tires doesn't really vary. A car is strapped down on a dyno, they don't have the tires sandwiched between rollers. If the tire is spinning the drum, the variance in tires wouldn't effect anything. The drum will be spinning as fast as the wheels, and the only thing holding the wheels to the drums is the weight of the car. Straps just keep the car from moving fore and aft. You wouldn't put down less power if you had drag slics, and wouldn't put down more power if you had "sticky as ice" tires.

Dynojet seems to be the most relaible and accepted numbers. On a Dynojet, a stock WRX puts down right around 150hp. STi puts down around 230. Forester 2.5XT puts out around 170.

Edit: Typo on WRX number.

Posted: Sun May 16, 2004 10:37 pm
by LegacyT
so basically you got around 220 chp. Would the MSD ignition help out alot in power?

MArk,

Posted: Sun May 16, 2004 10:41 pm
by BAC5.2
LegacyT wrote:so basically you got around 220 chp.
Sounds a little high. I made a typo, the WRX puts around 150 to the wheels. I'd say he makes more like 200bhp.

Posted: Sun May 16, 2004 10:48 pm
by LegacyT
Shit, I thought a wrx had 140 whp.

Mark,

Posted: Sun May 16, 2004 10:54 pm
by evolutionmovement
But there are lots of variables between dynos, daily conditions, and even operators that can cause more than enough variables to make HP comparisons between cars nearly pointless unless done on the same day at the same place, etc. SO what do those numbers really mean for purposes outside tuning? If you can hit the 1/4 in 13 flat, you know you can hit the 1/4 in 13 flat. I'm just saying that I prefer performance numbers to calculate, but maybe I shouldn't have as I don't really want to pull this thread off topic. (I'm giving it a go of trying that for once) :lol:

Steve

Posted: Sun May 16, 2004 11:41 pm
by LaureltheQueen
art pulled 255 in the stock STi wherever he dynoed

Posted: Sun May 16, 2004 11:47 pm
by FG!!
mTk wrote:Guys all guessed high :) Max psi turned out to be 9.3. Looks like FG gets the cookie :P

MK
mmmmm, cookie...... garble garble garble[/yoda]

Posted: Mon May 17, 2004 3:05 am
by vrg3
Phil - I meant the friction between the tires and rollers varies from dyno to dyno. Just like 128034710901 other factors, which means you can only compare dyno numbers if they all came from the same dyno.

Posted: Mon May 17, 2004 3:14 am
by BAC5.2
I don't quite see how though. The only thing holding the car down on the rollers is the weight of the car. How can the weight of the car vary from dyno to dyno? In the end, the rollers are still spinning the same speed as the wheels are.

Laurel - What dyno was he on? TurboXS is right down the street from me, and they put 230 down at the wheels on their dynojet. It's been a little while since I saw the graphs, but I believe the peak number was 230.