Faline

What is the best way to 1/4 mile launch a B5 with an APR Stage3, RS4/RS6 Hybrid turbos, and RS4 cams/intake?

-Quickly engaging the clutch and flooring it, bogs.

-Reving to 3K rpm and dumping the clutch is hard on the drive train.

-Reving and feathering the clutch, fries the clutch.

Any suggestions??

Thanks!

Snow Trooper

get a better clutch, hold at 4k, stomp to the floor when the light goes grean and slip the clutch out over the course of about half a second- one second.

btw i ran very similar hardware but way better software and ran consistent low 11s off the bottle, so i will call my method proven.

donromani

Yeh, what kind of clutch and flywheel setup are you using? Stage 2 or 3 I hope? Snowtrooper has far more experience on the track, but during impromptu street races away from a stoplight I find the best method is to keep it at about 3-4k and just let it drop in hard. You have to resist flooring it for a tiny tiny bit to avoid peeling out, so give it like 80% to let everything get spinning and build momentum, finish up with it on the floor. Once the car feels like it has inertia it's time to slam in second and there's no reason to use full gas at that point.

I guess it boils down to getting somewhat of a rolling start before you apply the full power of the motor to the drivetrain.

Vast RS6 with Vast stage 3 clutch and stock flywheel here.

.357

I guess my kevlar clutch could handle that.

slowEURO

n2mb launch control, set to whatever conditions allow leave the line in boost.

Faline

Thanks for all the suggestions! I have a Spec Stage 2 clutch. It isn’t overly sticky and easy to feather if necessary. The care really doesn’t come on until 3K RPM. So 3+K RPM seems like a good starting point off the line…

I generally don’t beat on the clutch to preserve it and the drive train, and I always double clutch and/or toe-Heal down shift.

So it sounds like there are better Stage III ECU upgrades than APR these days. What is the latest and greatest now?

Faline

When reving to 3 to 4K rpm, and then launching, sometimes the motor seems to start cutting out before redline, somewhere starting at about 5 or 5.5K rpm. Do you think this is related to traction, or other issues that require logging the car? This effect occurs on both race gas and street gas and programs.

When I easily let the clutch out near idle and gradually floor it before 2K rpm, it shoots to redline very nicely without any engine cutout.

I have a boost check valve set at about 1.5 to 1.6 bar, to avoid the typical spikes during hard shifts.

Any opinions would be appreciated...

Thanks

Faline

It appears the engine cutout is due to traction. The engine seems to be reving a little quicker than the tac under these circumstances. By easing into the gas more on 1st gear, rather than flooring it, and/or having better traction, there are no cut out issues...