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Discussion Starter · #1 ·
Generally I don't go WOT in first gear as it just results
in crazy tire spin. When I do I notice that the 1-2 shift
seemingly fails. It feels like it attempts to change
gears but then goes into neutral for a second before
engaging 2nd. So I figured this has to be the clutch
failing. This doesn't happen on a WOT 2-3 shift. Now
admittedly an optimistic though, I'm figuring that
there's just too much power for the stock clutch.
Anyone know what the maximum capacity of the
OEM clutch is?

So my first question is has anyone had this problem before?
I don't recall seeing anything about it. Those running
NOS, have you seen this? Anyone think my clutch is about
to take a dump?

And assuming that this is just a capacity issue is there anything
I can do about it (besides not going WOT). I haven't found
an aftermarket clutch available for our cars yet.

Or maybe I'm retarded and this isn't the clutch?
 

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Strange you should mention this b/c I was wondering about the 1-2 shift at WOT as well. Was screwing around last week on a VERY deserted road to practice my launches for an upcoming drag day and I would always bounce off the limiter. I'd shift around 7500-8K and nothing (also have a raised limiter ala Powerchip). Tried shifiting earlier and earlier, but it never seemed to work. Dunno if this is similar to your problem, but it's bugging the hell outta me.
 

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Discussion Starter · #3 ·
Strange you should mention this b/c I was wondering about the 1-2 shift at WOT as well. Was screwing around last week on a VERY deserted road to practice my launches for an upcoming drag day and I would always bounce off the limiter. I'd shift around 7500-8K and nothing (also have a raised limiter ala Powerchip). Tried shifiting earlier and earlier, but it never seemed to work. Dunno if this is similar to your problem, but it's bugging the hell outta me.
It may be similar. After some point it doesn't want to shift
immediately. At first I was curious if it had to do with wheel spin
and trying to shift. I was thinking that maybe when the wheels
were spinning that lose of friction cause the revs to shoot up faster
than the HUD could display. And when I tried to shift it was too
late? I tend to shift by the HUD and not the tach. I'll try to keep
an eye on this next time.

I need to experiment a bit more to figure out at what point it fails
to engage. In my case it's a pretty jarring experience. It really does
feel like the clutch slips and goes into neutral and then attempts
to engage 2nd again after about a second. The car jolts. It feels
different than the limiter.
 

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I can't say if it's the clutch but this SMG tranny holds up to more than what any of us are pushing. Aren't the G Power SC'd and Dinan and RD Sport strokers using it.
 

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I believe you guys are experiencing the additional rwhp caused my your mods. If you are getting to much wheel spin in 1st, you will not get a quick shift change to 2nd. The car bogs for a second, then shifts. Just a traction issue.
 

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Discussion Starter · #10 ·
I believe you guys are experiencing the additional rwhp caused my your mods. If you are getting to much wheel spin in 1st, you will not get a quick shift change to 2nd. The car bogs for a second, then shifts. Just a traction issue.
I do think your right but it's not bogging down...it's a pretty violent
shuttering. Well, for now I'll live with not being able to shift at or
near 8250 rpms in first. Not a huge loss unless it's a sign of things
to come.
 

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I believe you guys are experiencing the additional rwhp caused my your mods. If you are getting to much wheel spin in 1st, you will not get a quick shift change to 2nd. The car bogs for a second, then shifts. Just a traction issue.
I don't find this the case. I have shifted to second at a multitude of RPM's in first (highest 8400rpm), and every time it happens with a bang and I spin in second also. I don't think wheel spin is a factor.

This was with the conti's though. With the new PS2's I put on the car gets MUCH more grip. The shifts should be instantaneous.
 

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No problems with 1-2 shift @WOT @8,250rpm here.
 

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Sorry for late chime in, Steve.

I never recalled having that problem you described. In my case, I shifted roughly 8400-8500rpm at WOT(pedal fully pressed and no let-go movement anymore since ESS ecu tuned) and just brutaly into 2nd without and delay/lagging (my head just snapped). In term of power, you and me are very much the same ball park. May be your 3.91 differential???:3: That's the only thing i can think of.

No, never had that one. I only started noticing this after I had the
headers installed.
 

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Marshall// - try with MDM mode or with EDC off and see if it still happens. I think Multi may be right here...
 

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Discussion Starter · #16 ·
In MDM it doesn't have the problem due to reason stated by
Mike. I'll experiment more when the roads are dry. Kenny,
the 3.91 diff could be exacerbating the "problem". There's one
more thing I want to experiment with to see if it's causing the
stuttering. I'll let folks know what I find.
 
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