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By the best way I imagine you mean fastest way ?
The fastest way is by no means mechanically sympathetic,
quite the opposite, and will result in breaking things much sooner.
A fast but more mechanically sympathetic way is to let the clutch out a tiny bit to load up and take up the slack out of the drive train then let it all the way out.
This way is a bit slower but much kinder to everything as there are no sudden jolts to
any of the CV joints, gears etc.
you choose an RPM based on your set up, turbo, power etc, you don't want too much wheel spin but you don't want too much grip that you bog down.
What I'm saying is let the clutch out until it bites and starts the car moving then floor the gas and side step it, takes a bit of practice.
4-4.5k, bring up the clutch fairly quickly to where it bites, then slow the rate a fraction while you floor the accelerator and then make sure you engage the clutch before it spools up fully. Got my stock car under 5s 0-60 with this method but daren't do it with the RS2 kit on a stock 3B clutch
If it's wet, just hold it on the limiter and go for it
Cheers'en, AndyC
1994 ABY Coupe - Projekt Alpinweiss
it REALLY depends on what you have. i have tried quit a bit of things for launching mine..... and for MY setup, i find this has worked best so far. all four corners have drag slicks, and a 7.25" twin disc clutch with Sintered Iron discs. the Ceramic Bronze discs slip at this power level (>800AWHP)
i have launch control built in to my ECU. it revs to a predetermined level until the wheels roll more than 5kph i think, then rises up to the upper limiter.
i stage, making sure to be on the forward motion. i do NOT preload mine. when the lights show staged two bulbs, i floor the gas, and when the third yellow is fully lit i slip the clutch semi quickly but still slipping it. if i side-step it bogs and jumps and all 4 tires come off the ground most times. i launch with ~15-16 psi right off the line and it jumps up to a limited 26 psi in 1st gear.
i have my best times of 1.400 60' times and 0-60mph in 2.3sec.
A friend of mine used to Rallycross a Metro 6R4. His method to get her off the line was to per load the tranny by slipping the clutch slightly before giving it the large pedal. It's murder on the clutch though.
The rear shocks were connected together with a separate air line fitting which would be pre pressurised to 120 psi. This increased the bump settings to stop the rear of the car squatting on initial acceleration. There was a micro switch fitted beside to gear lever which, when 2nd gear was selected it would de pressurise the system to let the rear shocks do their think after that. It was space aged stuff back then.
For fun i used to preload to take up the drive line slack, then hold ~5500rpms and dump the clutch. That will give you a little bit of wheel spin in the front to prevent bogging down and away you go. From memory Paul worked out ~5500rpms was the sweat spot for a stock homefied car when testing the launch control. Basically you hold WOT with the ecu rev limiting at 5500 until you see .5bar, then dump it. Sounds fun but not very mechanically sympathetic.
Since my 1st gear has starting making grumbling noises when cold i've been a lot easier on it, basically drive off briskly but try to get the clutch fully engaged asap. Basically find the sweet spot between the shock of suddenly dumping the clutch, and slipping/cooking the clutch.
91CQ20v - Gone to a new home
93UR-S4 - The Magic Carpet
94S2Bus - The Emerald Express
I used the launch control on mine but last time I have done my stage 4 Soth Bend clutch .Any way no more SB on mine Sachs 07 and rs4 sprung disk is the way to go.6k rpm was the start on mine
Launch control on mine... Clutch down, WOT, the car will rev to 5k then build boost. At 1.5 bar side-step the clutch and prepare for self-inflicted whiplash
The wheels instantly bite, giving a little slip, as the engine bounces off the rev-limiter, then into second and you're already doing 30mph in what seems like a single second.
It's not mechanically sympathetic and i expect you'll go through tyres, clutch, rear-diff and driveshafts quicker
You could pre-load and hold it on the handbrake, then disengage the handbrake and side-step the clutch at the same point.
i forgot, i only drive mine with the rear diff locked and the center Torsen welded solid. and i take mine up >150 mph in 9 seconds, too, and the rear diff is fine. when you launch with the diff lock only partially engaged, bad things happen.
i REALLY think some of the breakage for big horsepower guys comes from the Torsen center diff modulating power back and front, and shocking the system and results in broken axles, etc.
I think that perfect launch depdends on each car / weight / power / grip, but should be something like - some slight wheels spin, not tu much to loose traction, or hit the revlimiter.
maybe like ?
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