Topic: Think I found solution for perfect 2 step launch

[MattM]

So...Im sure you guys have seen through a few threads I've had about the two times I went to the track.

First time I went I managed a 13.6 at 102 with my 2 step at 4000 rpms.  Well ,problem was that I went back last year with same setup and tried again but blew my rear diff out!

That sucked.  The reason this happened is that I was using the 2 step and basically dump in the clutch (spec stage 3 6 puck with lightened flywheel) and what happens is that it shocks the drivetrain which booted the car some (even the first time I went) and shocks the drivetrain.  The last time I went the tires didn't spin but instead developed.

So I still want to use the 2 step but its hard to try to slip off the 2 step (I tried it once) because you hold the hard pedal down and its a lot of preesure on your leg which just wants to let up. 

Well I think I found the solution!  Its called the clutch tamer a stand alone cylinder that goes under the dash and fixes to your clutch pedal.  You set it to allow the clutch to drop until maybe the last 10 percent the let out slower.  This allows your clutch to slip slightly/quickly and consistently.  This should allow me to drop the clutch off the 2step but still have the clutch cushion the hit enough not to bog the car or shock the drivetrain.

Has anyone else looked into this/know about it?

[Uranium-238]

I just feather the clutch when launching for the same reason, as you, only in my case it's axles I'm worried about.

Your clutch matters more for this though, is it designed to handle that slip? The Mcleod I've got in the Camaro is, you can smoothly let it out under load without smoking it.

[MattM]

Its a spec stage 3 (6 puck) with a lightened flywheel... I would assume it handles heat rarely well.  Don't know for a fact though.

[Uranium-238]

Wouldn't hurt to ask Spec, worst that can happen is they don't respond. I'm (quickly) learning the hard way that using aftermarket parts outside of what their original engineered purpose isn't great for their lifespan. (See the clutch master cylinder on my Camaro...)

If it's not designed to slip, that slipper could fry it and you'd just be better trying to find another way to launch softer. I don't know if you tune a softer launch without an aftermarket ECU or control box though, but that may be a better option.

[MattM]

Well....I know the material is pretty good at handling heat because of the first install I got on it.

I wanted to use the spec stage 3 with the stock flywheel, but the machine work on the flywheel wasn't done perfectly.  This caused the clamp pressure to be way subpar and as a result when I would floor it the low clamp would cause the clutch to slip for about 200-500rpms then it would catch in every gear.  That clutch never glazed or burnt up and I kept hitting on it to see if it just needed broken in for about 2,000 miles or so.  Still have that clutch in my shed. 

That said, I'm thinking the material is very durable for handling heat (if not it would have just slipped and slipped without catching).  Hell I'd feel comfortable putting that clutch back in with a perfectly machined flywheel. 

[Uranium-238]

Well there's an easy way to find out...drag the clutch and see if you smell anything...

[MattM]

I have and no I don't smell anything.

[Uranium-238]

Well that's a good sign.

Re-reading your original post, this thing will allow slip in all gears? Or just first?

[MattM]

Apparently it will allow a slight slip in each gear if you want it to, but if you don't push the clutch all the way down to the floor it won't "activate" it if you don't want the slip between gears.

[DeepBlueGXP]

Did your wheels hop on the run where your diff broke?

[MattM]

Did your wheels hop on the run where your diff broke?

Yeah so, I got new tires (nothing great) and the problem was that me and the other sky were the first to run in the morning (right after they sprayed all the tacky stuff).  I'd set the two step to try to overpower the back wheels to produce some spin at (4000rpms)  problem was that with how prepped the track was it just produced wheel hop instead.

If I would have been smart I would have driven through the water to try to lessen the initial hit some.

I've tried to slip the clutch a little with the two step but it's def hard to do, and if you do it too much you'll just burn the clutch.  That's where I think the clutch tamer would help because I could dial in the slip to make it slight and take some stress off the drivetrain on the launch.

[Uranium-238]

Wheel hop is a big issue in the 5th gen SS Camaros, I've even got it on the street a few times. Way back when Hot Rod hadn't been bought out by giant media conglomerates that cancel races for no good reason, they used to publish "What breaks when" articles:

http://web.archive.org/web/20170826104608/https://www.hotrod.com/articles/hrdp-1106-fifth-gen-camaro-parts-failure/

Point is, lots of things can lead to wheel hop, and I don't see a slipper clutch being a long term fix for what's really a bigger issue. It may solve the issue for now, but when you add more power, or do anything else to change the equation (wheels, tires, etc.) it may come back unless you start fixing what causes it in the first place.

[MattM]

Wheel hop is a big issue in the 5th gen SS Camaros, I've even got it on the street a few times. Way back when Hot Rod hadn't been bought out by giant media conglomerates that cancel races for no good reason, they used to publish "What breaks when" articles:

http://web.archive.org/web/20170826104608/https://www.hotrod.com/articles/hrdp-1106-fifth-gen-camaro-parts-failure/

Point is, lots of things can lead to wheel hop, and I don't see a slipper clutch being a long term fix for what's really a bigger issue. It may solve the issue for now, but when you add more power, or do anything else to change the equation (wheels, tires, etc.) it may come back unless you start fixing what causes it in the first place.

I only have two more goals with car (get best 1/4 mile time with trifecta on custom 93 octane tune) then (best time on ethanol)  same street tires.  After that, no more runs.  One of the other things I didn't get a chance to do was to lower my back tire pressure to around 21 psi (which could have dampened the wheel hop some).

[MattM]

Also keep in mind that with a conventional launch I don't have wheel hop but I don't get the benefit of the 2 step that said if I fully let off the clutch it completely shocks the drivetrain (which is what led to the wheel hop).  The best fix to that shock is to allow slight slip.  Right now without a mechanical solution to introduce the slight slip I would have to depend on my left foot which (if not done correctly or done for too long) could also introduce the chance of burning up my clutch which I don't want either.

That's why the clutch tamer is an obvious solution.

[DeepBlueGXP]

Yeah so, I got new tires (nothing great) and the problem was that me and the other sky were the first to run in the morning (right after they sprayed all the tacky stuff).  I'd set the two step to try to overpower the back wheels to produce some spin at (4000rpms)  problem was that with how prepped the track was it just produced wheel hop instead.

If I would have been smart I would have driven through the water to try to lessen the initial hit some.

I've tried to slip the clutch a little with the two step but it's def hard to do, and if you do it too much you'll just burn the clutch.  That's where I think the clutch tamer would help because I could dial in the slip to make it slight and take some stress off the drivetrain on the launch.

I had wheel hop to at first and let air out of the back to about 20 psi and they stuck better. Wheel hop will destroy a rear diff

[MattM]

Agreed!

[MattM]

Im looking at some other advice to soften the hit In reading about folks that use the 2 step and e-brake to preload the drivetrain which is supposed to really soften the hit.
I'm not quit sure how to do that though and there is conflicting info on how to do it.

[Uranium-238]

Im looking at some other advice to soften the hit In reading about folks that use the 2 step and e-brake to preload the drivetrain which is supposed to really soften the hit.
I'm not quit sure how to do that though and there is conflicting info on how to do it.

Usually that's advice given to avoid spinning, where you're worried about the sudden torque breaking the tires loose. As you release the brake, there's a "ramping" of torque instead of a shock load.

Go watch some Cleetus McFarland videos where he's racing Leroy. He does this when he launches.

Still won't prevent wheel hop though.

[Steelmesh]

Would suspension work help dampen the shock, like softening the rear and getting it to squat?  There is a picture somewhere of someone who knew how to drag race a solstice and nearly got the front tires up.  I did a google search cant find that photo, one of you all might know who I am talking about.

[MattM]

Would suspension work help dampen the shock, like softening the rear and getting it to squat?  There is a picture somewhere of someone who knew how to drag race a solstice and nearly got the front tires up.  I did a google search cant find that photo, one of you all might know who I am talking about.

DeepBlueGXP was the one who was able to do that.

[Uranium-238]

DeepBlueGXP was the one who was able to do that.

Yes, and on perhaps the best prepped track in the country. I think he had coilovers, but he'd have to answer that.

[Uranium-238]

Just had a thought: if your purpose for taking the car to the track is to have comparison data between modifications, consider using the trap speed instead of the ET.

Trap speed is generally less effected by a poor launch than ET is, and is usually used by racers as a gauge to the car's HP. You might be better served to spend your money on the upgrades you want, go make several passes with soft launches, average the trap speed and use that as your benchmark. If you weigh your car post run there are even calculators to help you approximate your car's HP.

http://www.wallaceracing.com/et-hp-mph.php

[Kelu]

We use Dragy, generally for 100-200km/h to measure the delta in power.
Just find an empty road and rip it, no hard launches, no track.

https://dragymotorsports.com/

[Steelmesh]

We use Dragy, generally for 100-200km/h to measure the delta in power.
Just find an empty road and rip it, no hard launches, no track.

https://dragymotorsports.com/

Haven't used one myself but a couple motorheads at work say they work pretty good.  I have one of those OG passport units, but my car has poly engine mounts and the kappa windscreen tends to resonate at low rpms so it has trouble functioning.

[MattM]

Just had a thought: if your purpose for taking the car to the track is to have comparison data between modifications, consider using the trap speed instead of the ET.

Trap speed is generally less effected by a poor launch than ET is, and is usually used by racers as a gauge to the car's HP. You might be better served to spend your money on the upgrades you want, go make several passes with soft launches, average the trap speed and use that as your benchmark. If you weigh your car post run there are even calculators to help you approximate your car's HP.

http://www.wallaceracing.com/et-hp-mph.php

Nah thats not why I posted the thread.  Im looking at stuff for launching the car.  I'm looking at stuff to yet the best launch I can with minimal drivetrain shock (which causes the issues that occurred for me at the track).

I was hoping someone with a Kappa might chime in who had experience with 2 step launches at the strip as well as experience with the clutch tamer but it looks like no one does.