Help with 1/4 mile ET please...

[Very-Rexy]

Not sure if this belongs here but...

My car made 367WHP//384WTQ. I took it to the track today for the first time and the fastest ET I managed was 12.71@111mph with a 1.8 60ft. Shouldn't it run faster with that trap speed? I have no idea what I did wrong. The car has 07 STi drivetrain without a DCCD controller but it was tuned on the WRX tranny. I don't know if any of that makes a difference. My buddy ran 12.6@108mph in his wrx with 320WHP. Can someone tell me what I might have screwed up on? Thanks.

* Registered users of the site do not see these ads.

[Patrick Olsen]

My guess would be the driving part.

You might try asking in the Proven Power forum, as that seems to be where people live their lives a 1/4mi at a time the most.

[Very-Rexy]

Originally Posted by Patrick Olsen

...live their lives a 1/4mi at a time the most.

LOL. Actually, I autocross mainly, but had some friends go to the 1/4 today and decided to run with them. Thanks though, I'll check out proven power.

[reddevil]

Trap speed is generally POWAH. ET is drivers skill combined with gearing, tires and whatnot.

I consistantly trapped 12.8 @ 112! But I was missing 3rd gear. So there are MANY variables in the actual ET, whereas the trap speed is just good proof of power.

[speedyHAM]

My bet would be that you need to shift faster and at the correct RPM. Look at your powerband in each gear and figure out where the best RPM to shift at is. For most WRX's, the best shift point is not at redline.

[jmlaser]

The wrx is a 5 speed,... you have a 6 speed,.... and it WILL slow down your ET. That extra shift costs ya aprox .2 if your quick

[STi Mikey]

Originally Posted by jmlaser

The wrx is a 5 speed,... you have a 6 speed,.... and it WILL slow down your ET. That extra shift costs ya aprox .2 if your quick

hmmm. Still, 111mph is a good trap. My last run last season

1.78 60ft
12.27 ET
111.12 Trap

(07 trans but I shift 5th when I hit 6k RPM in 4th)

It may not be your driving though as most would think. Every time I get a new map, I go out with my tuner onto a flat, str8 road. I launch the car and shift as fast as I can through 5th gear to be sure there is no shift knock. Shift knock is a really common problem that people seem not to catch. The car may feel good during a pull, but does it fall on its face for a split second when you shift???

[cvillesfinest]

your launch could factor in alot on your ET.. check your tire pressures.. takes time and practice to get your et quicker. like the guys said above, theres lots of variables that tie into it.

[Phatron]

Originally Posted by Very-Rexy

The car has 07 STi drivetrain without a DCCD controller but it was tuned on the WRX tranny.

Originally Posted by STi Mikey

Shift knock is a really common problem that people seem not to catch.

The car could probably use a touch up on the tune. The way you sweep through the cells and where you land after a shift are completely different on the 5 speed and 6 speed. There is a high probability that mikey is correct, with the shorter gearing on the STi the rpm and load drop way less than when shifting on the 5 speed.

Also, post up your 60 foot time. I bet half the problem is in the launch, 1/4 of the problem in the tune, and 1/4 of the problem in the shifting speed and correct usage of your powerband.

Whats your setup? If we know your turbo we can give you a better "approximate" shift point rather than just going to redline.

[Very-Rexy]

Originally Posted by Phatron

The car could probably use a touch up on the tune. The way you sweep through the cells and where you land after a shift are completely different on the 5 speed and 6 speed. There is a high probability that mikey is correct, with the shorter gearing on the STi the rpm and load drop way less than when shifting on the 5 speed.

Also, post up your 60 foot time. I bet half the problem is in the launch, 1/4 of the problem in the tune, and 1/4 of the problem in the shifting speed and correct usage of your powerband.

Whats your setup? If we know your turbo we can give you a better "approximate" shift point rather than just going to redline.

Wow this is great info. I'll ask my tuner about that. Never thought about that at all.

60ft for that run was 1.81.

Mods
DeadboltZilla 20g ported and clipped turbocharger
Hallman manual boostcontroller
TurboXS front mount intercooler
HKS SSQV
Power Enterprise 800cc injectors
Walbro 255 LPH fuel pump
Element Tuning turboback exhaust w/ divorced wastegate pipe
2007 STi 6-speed transmission
2007 STi Driveshaft
2007 STi Rear Differential
2007 STi Axles
2007 STi Hubs
2007 STi Rotors

The car was tuned by Scott at TopSpeed. On the WRX tranny it made 367WHP//384WTQ 20psi. Peak power was at 5700rpm and peak torque was at 4400 rpm. I was shifting at 6800rpm which I'm starting to think isn't right.