Slipping the clutch vs. Dumping the clutch

[Townson]

What are the pros and cons of each? I know that side stepping at a high rpm is likely to wreak havoc on the driveshaft and axles, but is it worth the risk for the sake of better 60' times?

I've been slipping the clutch at around 4800-5k and have a 2.09 60' to show for it, and an 8.77 1/8 mile.

Could side stepping at 5k get me a lower 60'?

Specs:
08 Gt
Airaid cai, Jlt catch can.
Bama 93r v2 tune.
Pypes o/r x-pipe.
Cobra jet springs, BMR lca's.
Racestar 15x8s and 15x3.75's.
Mickey Thompson 275/50/15 et streets, classic 165s.
3.31s.
5 speed.

I'm going with 4.10s in the future. I also know that I need "part x, y and z to be a serious contender."
I'll get to that later.

I'm asking strictly about clutch technique lol.

 

[Sactown]

side stepping the clutch is fine (thats what I did for years), you just need to find the sweet spot between bogging and blowing the tires up, a little spinning is better than bogging IMO

 

[mach828]

Slipping is better. And you have more consistent short times that way as well.
If you do it right you can launch the car and get it rolling out of the hole without ever seeing low rpms. You also control the wheel spin. I can add quite a few more lbs of air in my slicks, and cut better short times, by slipping the clutch. The front end lowers really smooth and the launch is less violent than a clutch dump.
Just takes some seat time.

 

[Townson]

I need to let some more air out of the rears. I'm running 22 lbs hot. Several people have told me that around 17 is where its at for the et streets.

 

[Sharad]

Dumping the clutch will just blow off your radials. If they were slicks, you could discuss dumping the clutch rather than slipping it.

That said, slipping is gentler on the drivetrain.

 

[Townson]

Alright thanks guys. I know an 8.77 doesn't seem like much, but I've outrun several ls cars at the strip and that makes me smile lol. It seems like the norm for intake and exhaust 3v's on street tires is around 9.1-9.4 up here and the same goes for ls1's, so I'm pretty pleased with the radials. Like I said, next up will be 4.10s, relos, and finally getting around to installing my wot box.

 

[NickD87]

I personally think what you're doing is wrong
I have had very close 60' times leaving at idle on street tires, slipping the clutch at 5000rpm just seems like unnecessary wear and heating up the clutch.
If you're not spinning with 3.31 its probably bogging,(I did with 3.55's) launch harder and with a little bit of spin you will probably end up running quicker

 

[Marble]

I always had great success side stepping the clutch. A good sticky tire and a very forgiving Mcleod twin disc clutch gave me 1.5 60' routinely.

 

[Tbone]

I dump the clutch with wotbox set at 2300 rpms. Got a 1.9s with crappy 285 35 r18 sumitomo htr zIII's.

 

[Townson]

So I got my et down to an 8.71 with a 2.02 60' by dumping the clutch at 4500 rpms. Tire psi was about 16 lbs hot. I don't know what the deal is.

Hell I've tried launching every way I can think of.
The only explanation that I can think of is that my suspension geometry is screwed up because of the Cobra Jets. I know for a fact that my lca's are at a FAR from desirable angle.

Thoughts?

I'm picking up better times as I go, but it's just from improved shifting technique I'm pretty sure.

 

[smoken1986]

Your gears are killing you. After switching to 4.1's I was running 8.6's on street tires with just catback tune and gears.

 

[Townson]

Yeah that's for sure. I'm going into 3rd like 40 feet from the line. Not pulling hard.

 

[Townson]

Got some BMR relos installed yesterday. Got them set in the middle hole. We'll see how I fare this Thursday at test n tune.