4wd4me

the time has come where we need to start launching our "new to us" EVO IX, it's still on the stock and original clutch, 55k miles....

what RPM is recommended, for setting the launch control/rev limiter at? 5K'ish?

this is for SCCA Pro Solo competition
we have two events to get under our belt (3 drivers) before we replace the clutch (later in July)

thanks for your input!

Doug
#56 STU

TxEvo8

iTrader: (5)

I would do at least 6k, I think that you'll bog at 5k.

MrAWD

Just make sure you get there on time on Friday and take bunch of the trail runs. Every surface is different and has different amount of grip. Even change from Friday to Saturday to Sunday changes this amount. So, do your practice starts and find the sweet spot for that event!

Fedja

4wd4me

that's some good advice, thnx!

Dallas J

iTrader: (1)

If you have 55k on the stock clutch DONT launch it. Usual life span for stock evo clutch is around 40k. Launching with that many miles is playing with fire.

rburris28

I went through 2 stock clutches in AS before switching clutches and adding a two step.

On the stock clutch I found revving to 5500 and then modulating the gas while releasing the clutch worked best on most surfaces and was adjustable on the fly. I don't think the stock clutch could hold many two step launches at 11 psi (what mine will build at launch) if it were new, much less with multiple drivers at 55k.

In fact, I would love to be surprised and hear that it lasted through one event however you do it.

Caffeine Slug

iTrader: (3)

I replaced my original 75k clutch before my first Pro Solo. I'm probably making average STU power, and at sea level events on a fresh clutch, the stock two-step limiter worked great. Ran through the whole El Toro Pro with two drivers, no problems. At higher altitudes and higher-grip surfaces I need to raise it, but I haven't ever done that.

I'll still launch it hard at events where it's beneficial, and the clutch is holding up fairly well about 15 months and 400 runs later. Occasionally someone will slip the clutch a bunch on a run, but once it cools back down again it's fine. I'm pleased with how long it has lasted given the abuse.

I would follow Fedja's advice if I was less lazy.

autoxer_minh

iTrader: (6)

Hey Doug,

I wouldn't bother with anything below 5k. What little experience I've had launching off the two step, even above 5k, I've had to modulate the throttle somewhat before going full throttle. I haven't tuned specifically for the two step launch so I'm not launching with as much boost built up as you can get. I'm at with 57k miles on the stock clutch and it's fine for regular autocross runs. I'm not sure it would last through a Prosolo though so I'm passing on those this season. Good luck!

erald01

iTrader: (5)

its abvious that some of you have no idea how to drive if you think that evos clutch lasts only 40-50k. I have an oem clutch with over 20 launches and still drives fine.

as for the OP set your two step at 5700-6000 rpm not any lower, so you can built some good boost before taking off.

4wd4me

Hey Mihn, others, thanks for the advice

we'll see 24 to 30 launches on one day (local event, 3 drivers) and 36, up to well over 40 at a National Pro weekend.... (so yeah, it's a concern).

Jeff_Jeske

iTrader: (66)

I have about 15 launches on my stock clutch and it holds 350whp just fine. It was good for multiple 1.6 sixties at the track as well but that and the occasional call out is the only time I stutter box launch the car.

I did have one issue.... When I was running 18" wheels with NT01 tires I couldn't launch the car without it slipping. I'm not sure if there was too much grip or too much weight but it wouldn't launch for crap. The next day I put on my BBS wheels with advance and the thing launched like a jackrabbit.

I'm still on the stock clutch with 24k hard miles.

b16a2delsol

iTrader: (1)

5k will bog, 5.5k is perfect, never needed to set it higher...

SS RX7 r2

iTrader: (1)

Hey Fedja.

Doug, be sure you let the clutch cool between multiple launches. I killed a new clutch at a Friday Pro practice, by doing 6 quick consecutive starts. It was gone by the super challenge on Sunday. I was told it's the heat that kills the disc. Now I only do 2, or rarely 4 practice starts.

Rick

Dallas J

iTrader: (1)

With the stock turbo I dont have bog launching at ~4500 not using the stock limiter. I am on a stock turbo and 24.6" tires (stock is 25.3") but the tires shouldnt make too much difference ( ~3%)

Thoe99

iTrader: (25)

I have an oem clutch. I'd guess over one hundred 4-5500rpm launches, autocrossing and drag racing. It still drives fine. The only time I had a problem was last winter, when the car was making 350tq--it was slipping at high rpms and I'd have to keep letting off and getting back on it to make it catch. I have 2 sets of wheels. With the larger set, I have to rev about 3-400rpms higher to get the same launch.