There's been some discussion recently about how to best get larger turbo 6 speed cars off the line hard.

Obviously conventional drag racing wisdom would be to use an automatic tranny (bleeder) with a stall convertor to allow the turbos to spool up. That option is not available to 6 speed racers (ie real men).

So how best to launch hard with those great big ugly laggy beasts that make 43 rwhp until 5000 RPM?

Forget launch control or traction control since those items are illegal in any NHRA class. And traction control won;t help you build boost on the line. What is available is a two step and antilag functions.

The two step is usually used via the ECU for two purposes. One is to limit how high the RPMS can climb during your burnout and the second is to allow you to floor the gas before the launch and let the engine sit at the predetermined launch RPM. Great tool for getting a hard consistent launch, not a whole lot of help in building boost with no load on the engine though.

Antilag is also used via your ECU. You can google for yourself how it works but be sure it accelerates wear on your turbos while it's being used. It does however allow you to build boost while stationary on the line ready for a hard launch.

When I say "ECU" I do not mean the OEM Motronic. I mean a standalone unit.

Now the question is, what can be done with the OEM ECU?

 

The mad scientist could tell us (Todd Knighton).

 

From what I know there's not really anything that can be done with the stock ECU. There simply isn't any sort of parameter for a 2-step or anything similar... At least from what I know

-Aaron

 

Is it possible to use an aftermarket ignition system like a MSD DIS4? I used one on my Turbo Eclipse back in the day, worked great!

 

pssssssht psssssssht.... Little nitrous always does wonders.



The easiest was i've seen to launch a big laggy turbo car is to roll up to the line, use the linelock (or e-brake) to hold it in place... rev it way up, slowly let the clutch out, to bump the car into the staging beams..

Get the revs where you want them for launch, let the clutch out just a hair to take the slop out of the driveline (unless you want to leave your tranny back at the line), on the 3rd yellow step off the clutch and put your foot to the floor. It should be making decent boost at a stop and build very very quickly.

You need a car thats setup pretty well to step off it that hard and not just blow the tires away though. Or in the case of awd a VERY stout clutch.

Watch the video of Garths car running that 7.98, thats how you step off the clutch at 6200 and hang the f*ck on.

 

Todd K looked into it for me and said VIA a acu motronic is really a no go...
as far as other ecus ????

 

Nitrous is hard to set up and get right. Especially on a big dollar Porsche engine. If you've got a 2ZJ bullet and you pop it, you just load another bullet if you know what I mean.

The method you described will build next to no boost on the launch.

 

Great post kenny...

What you really need is a built tiptronic box and a high stall baby

 

the thread's title is an oxymoron!!
Love you drag racing guys shows what man and machine can do where there is a will and desire, but this car certainly didnt start life out meant to be at the drag strip!
No flaming please, you know I love you guys, just being honest!

 

maybe a shot of NOS just for spool up.... electronically controlled... .6 bars cut off... that would probably do it....
But who is willing to NOS the car? not me.
markski

 

Yeah it's done that way a lot and especially on the supras but with the TT set ups it's not like they lag _that_ bad

Sorry guys the Tiptronic thing has only been proven to the 1/8th so that's all it's good for

 

I'm with Tom on this!

 

A 997 TT just ran a 9 second pass in streetable trim. But it's not a good drag racing car?

I beg to differ. Our cars ****ing ROCK at the drag strip.

 

Certainly the easy way to launch a larger turbo 996TT is to trick up an automatic tranny, use line locker/transbrake/stall convertor/antilag/twostep combination and just let it spool and pop the clutch. But I'm not interested in bleeders (no offence).

The Supra crowd have done the R&D and have worked out how to get a hard launch from HUGE turbo small capacity 6 cylinder engines. Yes using antilag and nitrous.

The Porsche drag racing crowd wil get there, it's only a matter of time. What's holding things back at the moment is the lack of ECU R&D.

Of course the driveline is completely underdeveloped at this point. the EVOMS half shafts have proven to be inadequate for hard launches and the Drexler gear is too expensive for most.

Fun times, fun times.

 

Mr Blonde,
Planning to take the 996TT down the same path as the M ??