View Full Version : Slip it or Dump it? M6 guys chime in!


Carter01
10-09-2008, 06:13 PM
After blowing up my old 10 bolt a few weeks ago I now have a Moser 9 on the way from EPP. My question is launching the car now that I actually can. In the past I always had to "baby" the old 10 bolt on my launches which would only net around a 1.85-1.90 60ft. I am ready to get on down with the 1.60 boys and girls so I can actually see what my car will do in the 1/4 mile. In the past I would always preload the 10 bolt until I felt the car barely move then I would launch the car so at least the drivetrain would have some pressure on all components. Now that I have the Moser 9 with the PST 3.5 DS I want to know the best way to launch the car for the best 1/4 times.
Quick Run Down - roughly 400rwhp street car, MT ET Streets, LS7 clutch kit, LCAs, PHB, SFCs, Adj TA, Moser 9.
Thanks!

tee-boy
10-09-2008, 06:16 PM
how do you pre-load the car with a clutch without killing the engine? i just don't see it.

kkslds
10-09-2008, 07:09 PM
how do you pre-load the car with a clutch without killing the engine? i just don't see it.

Releasing the clutch just enough to roll and take the slack out of the drivetrain so its not such a sudden shock on all of the driveline components.

Fast_94_Z
10-09-2008, 07:24 PM
what are you using for tires? slicks, drag radials, street tires etc?

daniel6718
10-09-2008, 07:27 PM
what gears?

Carter01
10-09-2008, 08:02 PM
factory 16x8 five stars, MT ET Streets (26x10.5x16), 411 gears, FYI - I do powershift the car.

1BADAIR
10-09-2008, 09:11 PM
both pedals to the floor and dump the clutch.
right foot shouldn't leave the floor til you see the win light

Fast_94_Z
10-09-2008, 10:31 PM
^^^ thats what i would do

DTB_LS1
10-10-2008, 12:09 AM
We have very similar setups and I was dumping the clutch at around 4800 until I gernaded the Tru Trac in my 9". My LS7 clutch was also starting to slip at the track. My car has a spool and 35 spline axles now and I plan on swapping out the LS7 clutch for a Mcleod twin disk over the winter and dumping it at 5000-5500 next year. BTW my best E.T. and 60' with the LS7 clutch and Tru Trac posi are in my sig.

tee-boy
10-10-2008, 10:06 AM
Releasing the clutch just enough to roll and take the slack out of the drivetrain so its not such a sudden shock on all of the driveline components.

ok. MAYBE slightly preloading the drivetrain. suspension would be a different story.

ndfrsd6
10-10-2008, 10:42 AM
im coming out at 5500 on a radial ,you cant come out on the limiter with a radial .....in my sig im on a radial at 5500 running a 1.57 60ft and my best is a 1.49 on a radial . i am switching to 28 et drags in the spring and coming out on a 2 step at 6000

BlackScreaminMachine
10-10-2008, 10:48 AM
A set of Bias Ply, and properly set up rear suspension and go off the limiter. I pulled a wheel with ease.

Carter01
10-10-2008, 07:15 PM
Thanks for the replies, I feel I'm really going to have to drive it like I stole it to bust 11s na. So far it seems that the vote goes to Dump It! Any other suggestions on the launch?

speedshifterNC
10-10-2008, 07:26 PM
nah...dump it..its so much more fun and now you don't have to worry about it..as much

1BADAIR
10-10-2008, 09:25 PM
very last pass on this vid is my car. I don't beleive in slipping the clutch.
http://www.youtube.com/watch?v=LrKPmqVLofk

Slvr00Bird
10-10-2008, 09:31 PM
very last pass on this vid is my car. I don't beleive in slipping the clutch.
http://www.youtube.com/watch?v=LrKPmqVLofk

What happened? Sleepz ownd me.. :confused::D

1BADAIR
10-10-2008, 09:55 PM
huh ?

gsxr1k2
10-10-2008, 09:58 PM
both pedals to the floor and dump the clutch.
right foot shouldn't leave the floor til you see the win light

I'm with him though not very good at it....

3DFORMULA
10-11-2008, 08:52 AM
both pedals to the floor and dump the clutch.
right foot shouldn't leave the floor til you see the win light

I'm with him on that also.

pddye
10-11-2008, 10:05 AM
When I had my 6 speed I dumped the clutch about 3800 to 4000 and let off the gas and used the clutch on every shift. I wasn't about to blow a tranny to knock a tenth of a second off. My best 60' was a 1.53.

tee-boy
10-11-2008, 10:53 AM
slip it. keeps the motor from bogging, reduces wheel hop, and improves 60'.

speedshifterNC
10-11-2008, 04:09 PM
slip it. keeps the motor from bogging, reduces wheel hop, and improves 60'.

and wears on the clutch..if you wanna slip it stay out of drag racing

N2RACINGLS1's
10-11-2008, 04:49 PM
I would have to agree with speedshifterNC.

When I ran my 6spd WS6 car I would launch at 3K and side step the clutch, granted it only ran 12.75 at 109+ MPH and only had 1,700 miles on it and it was mostly stock with the 10 bolt and DR's so I was easy on it. It now has 25,000 miles on it with the same clutch and stock rearend.

I would think with what you have and you are running ET Streets you should start somewhere around 3,800 RPM's and go from there. I have known several people that launch around 4K to 4.5K with your mods and tires.

N2

smokeum99ta
10-11-2008, 05:37 PM
and wears on the clutch..if you wanna slip it stay out of drag racing

So I guess you don't use the brakes at the end of the track, so you don't wear out pads :bang:.

I launch 6500-7000 depending on track conditions slipping the clutch, not riding the clutch. Instead of sidestepping off the pedal I let it out very quickly. That way has netted my best 60" of 1.32.

speedshifterNC
10-11-2008, 09:54 PM
So I guess you don't use the brakes at the end of the track, so you don't wear out pads .



there's only one way to get on the brakes and atleast 3 ways to engage the clutch so what's your point?

thats interesting that you "slip" the clutch as I've only heard that working with awd turbo cars

WS6TransAm01
10-12-2008, 12:12 AM
and wears on the clutch..if you wanna slip it stay out of drag racing

Every time I see posts like this, it makes me laugh... no one I have ever seen run sick times in a 6speed "dumps" the clutch. There is always a degree of slip.

If you have a good clutch, then slipping it will not be a problem. I slip the clutch on every 6000-7000rpm launch. I don't burn the shit out it but I do not dump it either. If you dump the clutch, the car will bog, or spin. If you slip the clutch QUICKLY if will keep the revs up and will be a smooth hard launch. The revs will stay up and carry the car nicely out of the whole.

I am by no means the end all be all authority of 6speed driving, but I think the video that has been posted on this forum many times of me driving my car speaks for itself.

smokeum99ta
10-12-2008, 08:14 AM
Every time I see posts like this, it makes me laugh... no one I have ever seen run sick times in a 6speed "dumps" the clutch. There is always a degree of slip.

If you have a good clutch, then slipping it will not be a problem. I slip the clutch on every 6000-7000rpm launch. I don't burn the shit out it but I do not dump it either. If you dump the clutch, the car will bog, or spin. If you slip the clutch QUICKLY if will keep the revs up and will be a smooth hard launch. The revs will stay up and carry the car nicely out of the whole.

I am by no means the end all be all authority of 6speed driving, but I think the video that has been posted on this forum many times of me driving my car speaks for itself.

Great explanation. Hopefully some of these people will learn from this post. Dumping the clutch is something you do to make the tires spin, like most of of did when we first got are new f-bodies.

speedshifterNC
10-12-2008, 08:48 AM
I guess it depends on your setup. I actually tried slipping the clutch at first to no aveil. I kept spinning or bogging. Then I dumped it and hooked hard and took off. So it looks like there is a time for both

tee-boy
10-12-2008, 09:46 AM
slip it gets me my best 60' and hence 1/4 mile times. and is easier on my transmission, rear-end, chassis, suspension, wheel studs, etc...

I'd rather change a clutch than a rear end and a busted torque arm.

Build a light weight car and slip the clutch. The lighter you get it, the more agressive you can be with the clutch.

Fast_94_Z
10-12-2008, 11:28 AM
Every time I see posts like this, it makes me laugh... no one I have ever seen run sick times in a 6speed "dumps" the clutch. There is always a degree of slip.

If you have a good clutch, then slipping it will not be a problem. I slip the clutch on every 6000-7000rpm launch. I don't burn the shit out it but I do not dump it either. If you dump the clutch, the car will bog, or spin. If you slip the clutch QUICKLY if will keep the revs up and will be a smooth hard launch. The revs will stay up and carry the car nicely out of the whole.

I am by no means the end all be all authority of 6speed driving, but I think the video that has been posted on this forum many times of me driving my car speaks for itself.

i agree with this. ill be slipping mine to some degree because ill be backing a lot of power with a big block and a turbo. wanted to do something different with my car then an lsx ot ltx and try to get close to the current 6 speed record.

speedshifterNC
10-12-2008, 07:34 PM
as long as it works I'll be side stepping mine...I love the feeling of hooking hard and cringing off the line. The op might as well try both to see what works for him as thats how we all found out anyway

1BADAIR
10-12-2008, 08:15 PM
I tried slipping before but was not very consistant.
this is from yesterday. clutch slipped but not cause I wanted it tooooo.
the spec III x-pad has had a long and abused life
http://www.youtube.com/watch?v=9kWyY_kNQHw

Carter01
10-13-2008, 07:09 AM
I appreciate the replies and many different views which each are revelant. I have tried both ways in the past but on different cars. Ex. my 88 hatchback 5.0, car maybe had 280 rwhp with minor suspension but from a 5500 drop it cut a best of 1.58, I have yet to duplicate such a 60ft with my 03 SC Cobra or any of my other cars including my Camaro which had from 100 to 200 more rwhp. However up until now I didn't have a choice but to baby it out of the hole. I will try both ways in the up coming weeks and post my results. I have set a goal of 11s na for my car and I'm striving to learn the best practices to get there.
Thanks again!

Grn4fbody
10-13-2008, 07:14 AM
Dump that bitch!

critter
10-13-2008, 02:49 PM
I have a RAM adjustable clutch because I can't cut a light and slip the clutch myself. My short before was 1.47x with the 11" cheater slicks spinning. Yesterday I finally got it backed off enough to start slipping and my short was 1.41x and it carried the front wheels for the first time ever. You will always et better slipping the clutch than the tires, and that is especially true with street tires.

speedshifterNC
10-13-2008, 06:20 PM
If you run a good pressure plate and stock style clutch, the clutch will slip a bit anyway. This works good up to a certain power point side stepping. Then I guess you have to slip it a bit as I haven't ventured into high horsepower territory

tee-boy
10-13-2008, 06:26 PM
I guess it depends on your setup. I actually tried slipping the clutch at first to no aveil. I kept spinning or bogging. Then I dumped it and hooked hard and took off. So it looks like there is a time for both

you kept spinning or bogging???? WTF does that mean?

And I guess you are running street tires , right?

mike c.
10-14-2008, 04:09 PM
I bring the clutch up just till it wants to pull. I hold it around 6,500rpm's and on 3rd yellow I dump the bit*h. 1.42 60's n/a.

Camaroholic
10-14-2008, 04:18 PM
I love the 2-step / clutch dump approach. Makes it simple and painless. ;) If you spin, lower the 2-step. If you hook, raise it the next pass. I usually ended up between 5800-6200.

Bitemark46
10-14-2008, 04:43 PM
It really depends on the tire and suspension. Bias ply sidewalls since softer than a radial need a good bit of "hit" to give them the rubber band effect. In addtion, you need a loose front end to transfer the weight and put instant load on the tires.

With a radial a constant hit (not extreme) yeilds a better 60. I used to run radials and was fighting the bog or spin. Too high or too low of rpms. A harder sidewall makes it more tricky to launch.

If the suspension gives good weight transfer than I'd dump it if running slicks. Slip it for radials. My $.02

-Mark

ZMONSTER!
10-16-2008, 01:54 PM
ok all of you who are slipping the clutch, what clutch takes well to being slipped?

PowershifterNC
10-16-2008, 02:17 PM
With a radial a constant hit (not extreme) yeilds a better 60. I used to run radials and was fighting the bog or spin. Too high or too low of rpms

Bitemark explained it for me...too high you spin...too low you bog.

I usually side step @ 4grand(stock rear) and that yields a decent hard launch with no bog...on MT drag radials

z28rob18
10-16-2008, 03:26 PM
id lik to c some videos from u guys that slip the clutch out to c how the car launches

tee-boy
10-16-2008, 03:57 PM
ok all of you who are slipping the clutch, what clutch takes well to being slipped?

stock clutch slips great, especially an old one. gets nice and hot too at about 5800.

Your 4L60E has clutches that slip too!!! And the older it gets, the more the clutches slip!!!

ZMONSTER!
10-16-2008, 04:23 PM
I dont have a 4l60!
What I meant is that I cant hook for shit just dumping the clutch. Ive got a 9 inch so thats no problem Im just spinning my et streets when I dump it, therefore I have to use the clutch to launch. So the question is what clutches hold up well when you slip the clutch during a launch?
Apparently centerforce isnt one of them....

chpmnsws6
10-16-2008, 11:06 PM
When you start to see the lights drop, put it on the revlimiter with your foot on the floor. When your ready to play, dump the clutch, hang on, and get ready to bang second like its your ex

Bitemark46
10-18-2008, 05:16 PM
I dont have a 4l60!
What I meant is that I cant hook for shit just dumping the clutch. Ive got a 9 inch so thats no problem Im just spinning my et streets when I dump it, therefore I have to use the clutch to launch. So the question is what clutches hold up well when you slip the clutch during a launch?
Apparently centerforce isnt one of them....

I don't think alot are designed for it.. Here's a spec stage 3 that I tried to slip/dump when I went to the track one day...

http://i174.photobucket.com/albums/w120/Bitemark46/Broken%20clutch%20and%20input%20shaft/miscpics001.jpg

http://i174.photobucket.com/albums/w120/Bitemark46/Broken%20clutch%20and%20input%20shaft/IMG_0024.jpg

http://i174.photobucket.com/albums/w120/Bitemark46/Broken%20clutch%20and%20input%20shaft/IMG_0025.jpg

I welded the PP to the disk to the FW. I was staged too long and it go hot. But let me tell you when I dumped it, it hooked hard as hell and the front had about a foot under with both tires. lol Then I couldn't get it out of first gear. For that I never slipped the clutch again.

-Mark

LM97Z
10-18-2008, 06:29 PM
Something has to give alittle to get the best 60fts. I netted my best 60ft. from a slipping cluch, NOT slipping the clutch, a "slipping clutch", this was on a stock clutch that finally gave up the ghost, i left at 3000 & let it out hard, normally i leave at 4000, it slipped horribly through 1st. but started gripping as it got hot, all the other times it would hook & bogg & 60ft. was always slower, i wish now i would have gotten a pair of Bias Slicks instead of the DRs. Now i'm going with a puck style cluch, i'm not going to leave any higher then 3000, i'll let the clutch out as quick as possible & go from there.

speedshifterNC
10-18-2008, 07:11 PM
It has a lot to do with weight transfer, suspension setup, and power. Until dumping stops working, it's too fun to stop

scott94z
10-18-2008, 07:30 PM
both pedals to the floor and dump the clutch.
right foot shouldn't leave the floor til you see the win light

I second that!

BADD SS
10-18-2008, 08:54 PM
Something has to give alittle to get the best 60fts. I netted my best 60ft. from a slipping cluch, NOT slipping the clutch, a "slipping clutch", this was on a stock clutch that finally gave up the ghost, i left at 3000 & let it out hard, normally i leave at 4000, it slipped horribly through 1st. but started gripping as it got hot, all the other times it would hook & bogg & 60ft. was always slower, i wish now i would have gotten a pair of Bias Slicks instead of the DRs. Now i'm going with a puck style cluch, i'm not going to leave any higher then 3000, i'll let the clutch out as quick as possible & go from there.

What was your best 60'? Judging by your sig, what your doing isnt quite working.... 3000 rpm is waaaay to low for a good 60' on a sticky tire with an M6.

smokeum99ta
10-19-2008, 08:10 AM
Slip it like I said before. Look at this list http://www.ls1tech.com/forums/showthread.php?t=809101 do you see anybody that posted on this thread towards the top that said dump it? A couple of us towards the top of that list said to slip it, hope you see the relationship between slipping the clutch and those faster times.