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Discussion Starter #1
So i have been meaning to do this for a while. everyday we see new dyno numbers, and new parts going on cars and new 1/4 times being posted etc etc. but we have no idea if the numbers are from a high reading dyno or a low. we dont really know if the new parts helped make the car faster, and a 1/4 time can be so much different if someone sucks at drag racing or if someone is really good!! plus the weather, track temp, tires etc.

so i wanted to make this thread to see how fast your car can actually move to tell us real numbers in my book. there is no lying to a data log! now of course you can cheat and do this going down a hill but come on, keep it legit!!

you can go ahead and post dyno numbers, mod list etc if you want. elevation, temp, wind, etc will play a role in this so if you want to wait till a cooler night with no wind, thats fine since we cant always predict the weather if this was a real race (street racing is illegal, dont do it ;) ). but you have to stick to these rules...

1. a super flat road; as flat as you can find, do it safely for you and others.

2. try to get around 2000 rpm, hold it there for a second or two like you are cruising. dont cheat and start pushing the throttle down early. in fact get to 2k, pull your foot off the throttle 100%, then mash the S out of it!

3. you have to be in 3rd gear so everyone is on the same page.

now this is no different than a tuner tuning your car on the street. they should be doing this anyways since a dyno room isnt that great with air flow and keeping everything cool. this takes all the guess work out of whos car can do what. you mashing the throttle takes zero skill so everyone should be just as good. just remember to be safe.
 

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Discussion Starter #2
ok ill go first. now im still in the process of tuning so ill see if i can improve and make the car "faster." you can see i started the log before i punched it and you can see boost was zero so im not cheating here. the car was able to go from almost 2k at 32mph to 6500rpm at 94mph in only 6.78 seconds. now who has a faster car and can beat that?

Temp: 60 ambient
Elevation: 1100 feet
Time: night time
Dyno: 330HP 388TQ for this log

https://docs.google.com/spreadsheet/ccc?key=0Ai9B4LLelFVNdE9OVmU2VHhwTEJ1Vy1ybFNmQUlJdmc
 

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Is it 3rd for all cars, or 3rd for WRXs and 4th for STIs (which I've heard requested more frequently)?
 

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you say street racing is illegal, dont do it but you went 94 mph on a public road. this is like a big dick contest.
 

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Not necessarily, you have to do 3rd gear pulls to log anyway...ive done several pulls in quiter areas by me to dial in erics maps more specifically to my car. I can see where your comfing from, its not street racing (nor do i condone it) but a lot of is do this anyhow for tuning purposes...
 

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Discussion Starter #6
Well actually I'm tuning my car like said. How else am I and the hundreds of tuners out there supposed to tune if we can't go over 5000rpm or 65 mph?? Lol a contest, are we not in a straight line bragging thread. Are there not power bragging threads on every forum? If that's your thought process I better never see you post a HP or a 1/4 time.
 

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Well actually I'm tuning my car like said. How else am I and the hundreds of tuners out there supposed to tune if we can't go over 5000rpm or 65 mph?? Lol a contest, are we not in a straight line bragging thread. Are there not power bragging threads on every forum? If that's your thought process I better never see you post a HP or a 1/4 time.
+1
Not too many shops gonna be off the beaten path rural enough to do a street tune to the point where it would be considered safe. Its a calculated risk just like any other time you decide to get behind the wheel of a car. I would think this would be better (in a way) since youll (hopefully) be more isolated from others on the road (especially late at night). Know the area, the traffic, the pedestrians, and account for other variables. Is it the smartest thing to do? Maybe not. Sure beats getting behind the wheel after having a drink at the bar though...
 

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synolimit, im just messing with you man. relax. who hasnt flew down the raod at triple digit speeds. its just funny the way you worded the first post. with the amount of cops ive seen lately by me, i gotta watch speeds these days. i saw 3 local cops and a state trooper today just coming home from work?? have fun and be safe!
 

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Discussion Starter #9
OOOOOOOO. see i was messin in that first post, thats why i gave that wink wink face.
 

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Discussion Starter #11
Damn so know one has a 3rd gear log?
 

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Discussion Starter #12
 

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i think i have some logs from my old E85 setup, il look tomorrow. and i can get one from my current Holset setup ;D



also dont know why most shops and tuners do 3rd gear pulls because 4th is actually closer to 1:1 maybe they want to show higher numbers ???

3.454 (1st) 1.947 (2nd) 1.366 (3rd) 0.972 (4th) 0.738 (5th) LGT/WRX 5 Speed (USDM)
3.636 (1st) 2.375 (2nd) 1.761 (3rd) 1.346 (4th) 0.971 (5th) 0.756 (6th) STi (USDM)

0n our 5 speed 4th is .028 over driven maybe a little extra load but not really , where as 3rd is .366 under drive ? ???
their was a debate in Nasioc proven Power section a little while back ?
 

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Discussion Starter #14
I saw that thread. Months of arguing I took from it 3rd for whatever reason is the best, safest, closest to acuate HP. I think 4th is more strain on motor and stuff, and makes HP read to high. Based on 1/4 times vs other cars 3rd on a good dyno should put out what you should do MPH wise. I know for saftey again, in this case you and not the car, 4th at redline is almost 120?? That's to much for the street.
 

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Thinking the same thing. Redline at 3rd is already 100+mph, and you get there faster than on 4th. It's just not feasible for a lot of locales, not that 3rd is always a cakewalk...
 

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Discussion Starter #16
100+? Damn son what redline you going to? ;)
 

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6.9k? That was before I realized the knock sensor stops reporting fbkc past 6k or 6.5k...and it's well past peak hp for me, so why bother? :)
 

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6.9k? That was before I realized the knock sensor stops reporting fbkc past 6k or 6.5k...and it's well past peak hp for me, so why bother? :)
Easily changed with OS tuning go to Ignition Timing - Knock Control click Feedback, Fine, and Rough Correction Range (RPM) and adjust Enabled Below and Disabled Above for all 3









and on the gear ratio issue, i dont want to bring that Discussion/Argument here but 70% of the post are from either Shops trying to sell Parts/Products and their services or customers that want to defend and Boast their high numbers.

iv had a few to many drinks tonight to fully explain but il give it a quick shot. im going to start by saying a dyno is only a tool and not consistant and reliable from one dyno to another, one car to another, or even one pull to another.

you final drive (wheels tires ring and pinion) is fixed and non variable. the DYNOS drums weight and diameter are fixed and non variable.


Here is how a dyno works thank you Wiki
First it is important to have an understanding of how DynoJet gets their horsepower numbers. Power in mechanical terms is the ability to accomplish a specified amount of work in a given amount of time. By definition, one horsepower is equal to applying a 550 pound force through a distance of 1 foot in one second. In real terms, it would take 1 HP to raise a 550 pound weight up 1 foot in 1 second. So to measure horsepower, we need to know force (in pounds) and velocity (in feet per second). Dynojet's inertial dynamometer measures power according to the terms just described. It measures velocity directly by measuring the time it takes to rotate two heavy steel drums one turn. It measures force at the surface of the drum by indirectly measuring it's acceleration. Acceleration is simply the difference in velocity at the surface of the drums from one revolution to the next. The force applied to the drums is calculated from acceleration using Newton's 2nd law, Force = Mass * Acceleration. Since the mass of the drums is know and acceleration has been measured, Power (horsepower) can now be calculated. Torque is then calculated using the horsepower number: Torque = Horsepower * 5252 / Engine RPM.
therefore you want to achieve a 1:1 drive to try and determine a "Accurate" number, by adjusting the gear ratio in the the transmission from 3rd 1.366 to 4th 0.972 you have gained a mechanical advantage and skewing the numbers and are no longer telling the "True" horsepower of the engine and are creating a artificially inflated number.

their are loads of other factors that play into a dyno like Calibration, Correction factor, and other factors that most dynos cant replicate like weight transfer, vehicle weight, wind resistance, drag, ect. unless you have a F1 Budge
 
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