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Perfect Launch?

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Old 09-16-07, 06:47 PM
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Perfect Launch?

So i've tried searching for the formula, but couldn't really find any good results. Only one i found said they dropped it from 6 & 5k revs, which to me seems kinda suicidal. So my question is, for a perfect launch from a fairly stock s5 Turbo, what should i do? Only mods are turbo-back exhaust(3"), pretty sure the car has a heavy duty single plate clutch and that's about it. Any help is good, taking on my friends dc5r again(won the first time) but his take off was pretty scary until i hit the magic 3rd gear.
Old 09-16-07, 07:53 PM
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There is no one perfect launch formula because it's different for every car. It depends on the powerband, weight, gearing, tires, wheels, surface of the road, etc, etc, etc.

Just try out a few different ways of doing it and you'll find what's best for you.
Old 09-16-07, 08:04 PM
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it really depends on a lot of things, thus there isnt a "perfect launch" formula. how good your tires are, how sticky or slick the road is, whether theres a grade, outside temp, tire temps and pressures, how good your clutch is etc...

In general tho, for a turbo, around 3-3.5k is about right. 5-6k is WAY too high for the street, you'll just convert your rear rubber straight to noise and smoke without the byproduct of acceleration
Old 09-16-07, 10:13 PM
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Originally Posted by toplessFC3Sman
5-6k is WAY too high for the street, you'll just convert your rear rubber straight to noise and smoke without the byproduct of acceleration
unless you do a little clutch slip..
Old 09-16-07, 11:07 PM
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yea, but i doubt you'll actually accelerate any more quickly than you would with a 3.5k launch, and you'll be wearing both the tires and the clutch more severely. Maybe with an NA you might, but with my turbo on stock boost, im seeing all of that by 3k, and the OP specified a mostly stock TII
Old 09-16-07, 11:13 PM
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On my stock TII and limited number of actual launch attempts, I'd say that 3.5-4k range is pretty spot on, plus I've seen that noted other places, too. And even at that point you can burn up the tires quite a bit if you just DROP it.
Old 09-16-07, 11:31 PM
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The car is not moving, the engine is. Unless you can find a way to run a 0 rpms something is going to slip ether the tires or the clutch...your choice. I prefer a mix of the two. Different traction is found both on the road/tires and in cluches.

It is an imposible question to answer, you will just need to determine what is more importaint to you based on what you have. The only goal is not to bog down by letting the clucth out with more force than the engine is making.

Try reving to 4-5 k and practiic how fast you let the clutch out...some will slip it while others will drop it.

Hope that helps, GL
Old 09-17-07, 10:33 AM
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with decent tires about 4k in my NA was good.
Old 09-17-07, 03:28 PM
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Originally Posted by toplessFC3Sman
5-6k is WAY too high for the street, you'll just convert your rear rubber straight to noise and smoke without the byproduct of acceleration
LOL! That's great!

Anyway, I always launched form about 4k in my N/A....till I broke the front diff mount...WTF MAZDA!?
Old 09-17-07, 03:53 PM
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It definitely depends on your setup.

My standard is a quick slip from 5k, but I have decent tires. On a really hot day, sometimes I'll dump from 7k without any wheelspin.

Then again, I had a stock S5 NA motor with drop-in filter and full exhaust.
Old 09-17-07, 05:33 PM
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try it all man, everyone's launches will be different. some feather the clutch, others drop it.

I would normally rev to 4500 then drop the clutch and WOT. Minimal tire spin and full grip on nice 225's all around.

At the track you can rev a lil higher due to sticky asphalt (or whatever it is). On the streets you're gonna get pulled over so I wouldn't try it.
Old 09-17-07, 09:17 PM
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Well i wanna test it out, but don't wanna risk damaging my clutch or anything like that. Got hit 2 weeks ago and still waiting for the repairs to get done, so i don't want any more dramas for awhile.




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