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davkav
08-21-2009, 01:46 AM
Quick question,

When you guys are launching do you generally bring the revs up and let the clutch out instantly or do you ease it out aggressively?

Reason I ask is mate of mine was driving my car last night and I said fire away - launch it at the lights. Next thing I know the car is darting forward as he literally just took his foot off the clutch at 3k+rpm.

This has to be bad for the clutch/engine/mounts right?

And yes I did go mad at him, the idiot

ed1380
08-21-2009, 03:19 AM
ease it out. controlling throttle and clutch

bob12312357
08-27-2009, 09:06 AM
Easing it out is gonna weld the clutch to the flywheel unless you got a Puck. I just side step it. Our drive train on the 1.8t's can take i and are very strong.

bl0wn3ur0
08-27-2009, 09:15 AM
Slipping the clutch is going to severly affect the life of your clutch. All of the drag race guys on AZ dump the clutch. No matter which way you do it your affecting the longevity of certain parts.

mike-2ptzero
08-28-2009, 01:56 PM
Always launch it by releasing the clutch quickly. Best thing to do is to bring the clutch up so that it is just before the engagement point, then release it quickly by just bending your knee. I have been drag racing A4/S4's this way for 9 years.

Slipping doesn't make the car launch faster and it just produces heat which is never good.

EtanClan
08-28-2009, 02:06 PM
I've tried launching a couple times on my stage 2 B5 S4, and by a couple times I really mean twice cause I didn't want to put any excessive wear on the drivetrain/clutch, so I haven't really had much experience.

But I had problems just dumping the clutch..I'd get the revs up to like 2-3k and then simply let go of the clutch and my revs would drop really low causing me to bog. What am I doing wrong?

I've heard that AWD cars often NEED to slip the clutch to launch because they can't put enough power to the ground to keep the RPMs high after dumping the clutch (aka no wheelspin).

I know it's been discussed a million times but I always see mixed responses. Does anybody have proof or a definite answer??

bob12312357
08-28-2009, 02:35 PM
I've tried launching a couple times on my stage 2 B5 S4, and by a couple times I really mean twice cause I didn't want to put any excessive wear on the drivetrain/clutch, so I haven't really had much experience.

But I had problems just dumping the clutch..I'd get the revs up to like 2-3k and then simply let go of the clutch and my revs would drop really low causing me to bog. What am I doing wrong?

I've heard that AWD cars often NEED to slip the clutch to launch because they can't put enough power to the ground to keep the RPMs high after dumping the clutch (aka no wheelspin).

I know it's been discussed a million times but I always see mixed responses. Does anybody have proof or a definite answer??
My car has 140K miles on the stock clutch and stock turbo with all the supporting mods. It's a 1.8T and it will spin hard all seasons to a road speed of 3500 in first then catch traction smoking many faster cars off the line,shift into 2nd and a city bus would pull ahead.lol It does launch hard though Brind your revs up,2500 Rpm is barely idle. I don't know where on an S4, but I launch around 5500RPM. Push clutch in,put car in 1st. Bring clutch just below engagement point. Bounce the revs around at around 5K. On the bounce your gonna launch, put your foot 2 the floor on the upswing of the revs and side step the clutch with your foot still holding that gas pedal 2 the floor. My clutch I don't think even realizes its been launched a couple dozen times all past 100K miles.

Haenszel20v
08-28-2009, 02:45 PM
I've been revving to about 4k... put the throttle all the way to the floor and drop the clutch when the needle hits 6500rpm. Scoots outta the hole nicely.

Havn't broke anything doing that, but I did fuck up 2 first gears trying to slip it.

mike-2ptzero
08-28-2009, 03:18 PM
I've tried launching a couple times on my stage 2 B5 S4, and by a couple times I really mean twice cause I didn't want to put any excessive wear on the drivetrain/clutch, so I haven't really had much experience.

But I had problems just dumping the clutch..I'd get the revs up to like 2-3k and then simply let go of the clutch and my revs would drop really low causing me to bog. What am I doing wrong?

I've heard that AWD cars often NEED to slip the clutch to launch because they can't put enough power to the ground to keep the RPMs high after dumping the clutch (aka no wheelspin).

I know it's been discussed a million times but I always see mixed responses. Does anybody have proof or a definite answer??

Too low in the rpms. Were you holding the rpms at 2k-3k rpms or were you at wot and just released the clutch between 2k-3K?

Slipping the clutch is something you do to reduce wheel spin on a FWD/RWD car, not something you want to do on a AWD car which likes wheel spin not clutch spin.

I would say 1.54 60 ft times in a AWD BAT A4 1.8t is pretty good proof. lol

Here are a few vids

http://videos.streetfire.net/video/Audi-A4-running-10s_163726.htm

http://videos.streetfire.net/video/First-round-of-in-True-at_201467.htm

http://videos.streetfire.net/video/Slipping-clutch_694950.htm


All of them were done launching at WOT and dumping the clutch.

EtanClan
08-28-2009, 06:46 PM
Gotcha...thanks guys. I was probly just being too cautious [:p] I'll bring the revs up next time.

mike-2ptzero
08-28-2009, 07:11 PM
Gotcha...thanks guys. I was probly just being too cautious [:p] I'll bring the revs up next time.

Yeah when it comes to launching our cars you cant be afraid, just have to let it all hang out.

andyrew
08-29-2009, 10:52 PM
Ya you cant pussyfoot it.

Nail the throttle and drop that clutch. In my BT 1.8t I blip at 4k then go WOT and drop it at 5-5.5k.

I would guess with the S4, if you went full throttle at 2.5k or off idle and dropped the clutch at 3.5k you should launch fairly well.

davkav
08-31-2009, 01:18 AM
hmm seems my thinking was wrong then.

Does dumping it too quick not cause excessive strain on gearbox / drive shafts or mounts?

mike-2ptzero
08-31-2009, 06:58 AM
hmm seems my thinking was wrong then.

Does dumping it too quick not cause excessive strain on gearbox / drive shafts or mounts?

Any way you launch it puts strain on the driveline.

sittinherebored
09-19-2009, 11:03 PM
i held 4500 and didint drop but was aggresive and got a very good launch. i also went to 6300rps for the first time. im very paranoid about breaking stuff

Mantis
10-01-2009, 04:51 AM
I like to side step the clutch at 3.5k while going WOT, this is just for showing off for friends. At the track I am leaving at 4.5-5k, getting 1.73-1.75 60s consistently with my big fat A6, and yes this will definitely stress your mounts

7speed
10-01-2009, 06:51 PM
I have recently found that the sweet spot for my car is 6600 RPM. I have also discovered that get turbo surge when I shift high in the RPM band. My target PSI is 20-21 and sometimes I end up with like 25-26PSI !

mike-2ptzero
10-01-2009, 08:07 PM
I have recently found that the sweet spot for my car is 6600 RPM. I have also discovered that get turbo surge when I shift high in the RPM band. My target PSI is 20-21 and sometimes I end up with like 25-26PSI !

If you get surge when shifting you dont have a big enough BPV/BOV.

7speed
10-03-2009, 10:11 AM
oh okay I guess its time to upgrade. Im running a forge 004

ZMEY
10-04-2009, 12:44 AM
op your car bogs, because your right foot is not fast enough on gas. be in a little higher rpm like 4k and when you drop the clutch floor the car simultaneously. but again you have to find the spot and use your feelings. if you scared dont do it at all. if you wanna do it dont be scared, because that will mess up for you if you are very nerveous.

mike-2ptzero
10-04-2009, 07:27 AM
op your car bogs, because your right foot is not fast enough on gas. be in a little higher rpm like 4k and when you drop the clutch floor the car simultaneously. but again you have to find the spot and use your feelings. if you scared dont do it at all. if you wanna do it dont be scared, because that will mess up for you if you are very nerveous.

It is just easier to go WOT first and well below your launching rpm. This way the throttle is fully open, rpms are rising quickly and then you just release the clutch all at one time at the rpm you want to launch at. This makes launching a AWD turbo car very easy since there is a much lower chance of screwing up.

ZMEY
10-04-2009, 10:55 AM
It is just easier to go WOT first and well below your launching rpm. This way the throttle is fully open, rpms are rising quickly and then you just release the clutch all at one time at the rpm you want to launch at. This makes launching a AWD turbo car very easy since there is a much lower chance of screwing up.

good point. there is diffrent techniques, to each his own. just gotta try all of them out, and see what works best for you.