Gary Z

My brief drag racing experience has convinced me that I will never significantly lower my sixty times until I am willing to slip the clutch and stop spinning the tires (MT 275/50R15s). After toasting my stock Z06 clutch recently, I selected a Ram HD replacement because I expect the sintered-iron friction material will absorb the heat of slipping during launch better than most other materials. I am asking anyone who is familiar with the Ram HD if their experience supports my expectation. How much punishment can it take?

tim99ws6

iTrader: (31)

I dont see a torque arm in your setup. You should be able to easily hook up on MT 275/50's with the power you are making. I personally run the HD clutch, and it has handled everything i throw at it so far. my car is approx. 3600lbs, 430/430, and launch off the 2-step at 6000+ rpms.....

it should have no problem with your setup

Gary Z

Tim, thanks for the reply but I’m still confused. I guess I don’t really know the meaning of “hook” I have assumed that “hook” means “minimal wheelspin”. If you launch at 6000 RPM and don’t bog, then either the clutch must slip or the tires will spin. Do you deliberately slip the clutch or do you “dump” it?

tim99ws6

iTrader: (31)

i dump it, wheelspin is NOT a bad thing, it's actually a good thing to a certain extent to keep some mph in the car. What exactly is your launch technique, and what tires are you running?

Gary Z

So far, I’ve just dumped it, anywhere from 2000 to 4000 RPM, and floor the throttle. My tires are MT 275/50/15 ET Street Radials at 14-16 psi. My sixty is fairly consistently around 1.91 with a best of 1.88. Occasionally, I spin so badly that I have to pedal it through first gear and my sixty will be more than 2.0. I have stock rear suspension (Spohn LCAs on the way) with new Bilstein shocks. Although stock, my suspension is tight and I have no wheel hop, just too much spin. I also have a right-rear airbag that hasn't been much help.

1QuickT-A

iTrader: (12)

Something is wrong here.. lol With the minimal power that you are making you should be able to dump the clutch off the freakin rev limiter and still hook up just fine. If you are spinning with a measily 2k-4k clutch dump then you need some suspension work BADLY!! I would play with tire pressure a little bit and do a good burnout. Also play with the air in the bag. If you have that bag screwed up it can totally fubar your launching..

I used to leave the line at 5500+rpms in my heavy *** LT1 T/A.. I was running E.T. Streets and sometimes slicks. I always got 1.6X short times out of it with about 380rwhp and 4.10 gears.. Totally stock suspension minus the front sway bar. This was with a SPEC Stage 5 clutch that had ZERO slippage.

Gary Z

I agree and have tried most of the things you suggest, with two exceptions. You said you used ET Streets or slicks, my tires are Drag Radials. And I have not attempted to heat them. I do a dry hop just to clean them off. And one other thing. I run at Infineon on Wednesday nights. I am not alone with this problem. The quickest guy with a car similar to mine says he slips his clutch.

PlatnumStatuz

iTrader: (6)

Infineon has no track prep on wed. nights.

tim99ws6

iTrader: (31)

get the tires wet in the burnout box....pull forward out of the box....do a GOOD burnout the first run of the night....after that pass, just do good enough of a burnout to get some hazy smoke out of the tires....


Understand that MT drag radials hook every bit as good if not better than ET streets

glennster

iTrader: (1)

I have a pretty much stock weight car except for big n littles alike to run the car as it comes off the street.I have the smaller MTs and to assure that I can probably drive home,I slip the clutch.I have the Ram HD with billet flywheel and holding it about 3.5K I give it a quick clutch slip and floor it at the same time.I can usually get a high 1.7 or bottom 1.8 and run high 11's.The clutch will take it even on hot laps,great setup for street/strip.

1QuickT-A

iTrader: (12)

very good advice here.. you definately need to do some sort of burnout with the m/t drag radials.. a simple dry hop will not do you any good at all with those tires.

CamTom12

iTrader: (1)

Agreed with Tim

Gary Z

This is what I was hoping to learn - thanks, Glennster. And thanks to everyone for your comments and suggestions – you have restored my delusions of quickness.

AINT SKEERED

iTrader: (2)

Not a fan of slipping a clutch at all. I also dump the clutch anywhere from 6000-7000 rpms and that will get me my 1.59-1.61 60 ft's. I do have an aluminum flywheel so that is why I go over 6000 rpms to make up for it.

On my Nittos, I have pulled a best of 1.64 on 315x35x17's and 1.67 on 245x50x16's by just bringing the revs to 4000 and when you let off the clutch(dump) hold the throttle at the same point untill just before the car is going to bog and then hammer the gas.
THis is better on clutch and other parts then slippin imo.

Gary Z

When you dump the clutch at 4,5,6000 rpm and the engine does not bog, something is slipping during launch - either the wheels spin or the clutch slips or both. My scanner data shows that my clutch does not slip and my wheels spin. My spinning wheels produce very little thrust. When I spin, I ease out of the throttle until I reach a point at which the wheels generate a strong seat-of-the-pants pull. The overall result is a 2.3 second sixty. I assume that low sixtys are the happy result of minimal wheel spin combined with some clutch slip which may be unintended and therefore unnoticed.