Launch technique?

Depends on the car. My GTM I can just nail it at 4500 and dump with full throttle. No wheelspin or clutch slip and it just goes. A friend has a Clan Crusader with rear mounted Honda Blackbird motor and 10 inch wide rear slicks. It can leave the line better than a single seater and he can be as aggressive as he likes with it. It's so light and has so much traction. Conversely, everyone I know with a 7 type car has to nurse it off the line and juggle the throttle against wheelspin. FWD is even worse.

Try and look at the question here above. It may help you regarding this thread....

Notice this above, he wants to go from zero to x as fast as poss. Nobody mentioned or cares about longevity, normal driving etc. It does not belong in this thread.

Yes really, a sidestepped clutch hardly heats up or wears at all. It is not the fastest way but it saves the clutch. If you are going to slip the clutch you may as well slip the tyres as well as the heat loading is split.

not unless you drive like you're in a grand prix each and

See ist question again. Nobody said anything about "every time you are out on the road" and in any case that would be his business.

My licence is actually now clean, and 65% no claims.

Listen, thats not poss. If there really is nothing slipping then it MUST have just stalled? You must be getting some of one or the other?

A friend has a Clan

I see the old Father Jack is starting to show his face ;)

You are both right as far as I am concerned and in relation to the question, JackH is answering my question from the perspective standing starts on the road and Burgerman is describing the best way to get great 1/4 mile/race times although me thinks I will need an uprated clutch ;)

Yeah baby!

Have you been wacked in the head and now your IQ is halved? Drunk? Taking the piss or is someone else on your PC?

We are not talking about my gti here.... just how everyone launches their cars.

So in fact he's actually goalpost shifting from something he has shown he knows very little about to something he does know about in a vain attempt to gain some credibility?

Launching - WITH CARS.

It doesn't actually say anywhere about launching with cars, although I have to say that is fairly reasonable to assume that is what I meant...

All of the above?

Well a baseline of what is being launched would help. The technique for a 5/95% front/rear mass split slider clutch top fuel dragster is somewhat different to a 35/60 or 40/50 mid/rear engine road or single seat race car, which is something different to a 50/50 front engine rear drive car. None of which are any use to your FWD car as it's already riding the wheelie bars excessively hard. As launching is only really applicable to drag racing there are changes depending of if street or drag tyres being used.

Download a copy of cartest, stick a few cars in and it will tell you best launch method - clutch dump, slip, or brake torque.

Who let Ali G in?

Same physics, same thing, just different amounts of power, but some cars have more than others too.

Thy simple physics involved does not care how many wheels you have.

Sounds like it has a dodgy Rover clutch to me ;o)

It won't have been designed to cope with anything like the shock torque it would receive in a rear engine, rear drive car on a high-revs clutch dump.

Mind-you, it sounds like it slips by just the right amount.

Cheers,

Colin.

the MR2 needs quite a lot of dedication before it'll wheel spin. i have accidently smoked the tyres outside my house when i was late going somewhere once. didn't think it had enough power to smoke the tyres and crawl along slowly making lots of smoke but it errr has :) still my tyres on the rear are pretty new so i wanna keep them that way so never launch hard at all now, clutch on an MR2 is a costly thing to replace!

Loose surface normally.

Track day? As a normal start.

Yes it does. As I understand it, you get the best traction when the wheel is turning slightly quicker than the car is moving forwards (and when braking, when the wheel is turning slightly slower than the car is driving). Failing that, applying as much power as you can without spinning a wheel is the way to go.

A mate of mine reckoned there were two fast launch techniques for his Westfield. Either start it and get both wheels spinning or pretend that you've a copper behind and get no wheelspin.

Each car is different. For ours, using over 4,000 rpm was pointless on the standing quarter mile. You just wheelspin the excess away. Between 3,000 rpm and 4,000 rpm worked the best.

For a fast start on the road, get it rolling then nail it. This makes you look less like an idiot. :)

Not on a front wheel driver. You'll wheelspin and wheelspin and wheelspin and eventually move off. :)

You may also damage stuff, like drivetrain components and engine mounts. That's how I broke an engine mount on the Ka. ;)

Yeah - you're right, obviously. But the lightness of the thing means that it doesn't need much effort to overcome the inertia and get it rolling. The wheelspin and clutch slip really is so slight as to be immeasurable. Another friend at the sprints has his wife record all the stats as the day goes on. The GTM with it's titchy little K series is pretty much up with the 4wd cars between the start line and speed trap from a standing start. Obviously, they annihilate it after that ;-) but it really is very very good on bottom end acceleration. In a similar vein I did start line duties at my club's hillclimb this week. All of the above was so very evident. 300bhp MR2 had a tenth of the wheelspin of a 1300cc polo. 2.0 zetec powered tiger 6 was somewhere between in terms of spin and actual acceleration. This was in the damp right enough.