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Old 05-06-2009, 10:37 PM   #38 (permalink)
travisjb
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three potential contributing factors... 1) SRM, 2) heavy flywheel, 3) slightly mis-timed pedal coordination...

as for 1, i have no data to confirm that SRM would hold the revs higher when up-shifting but it makes some sense. imagine you are accelerating and in the next second you will go from 55 to 60 in 2nd, as that's happening, you press the clutch and start moving the shift lever... SRM sense that you are 'passing the gate' for second gear and b/c you are now going 60 as you 'pass the gate' out of the gear it momentarily thinks you may be going into that gear and ups the revs... then you're on your way to 3rd and SRM targets a lower RPM but the damage was done... just a theory

thing 2, I think this is definitely an issue... i agree, even with SRM off it happens... pushing in the clutch allows the engine to rev without the rest of the drivetrain to slow it down and the momentum built up in the engine internals and flywheel is so great that it gathers RPMs as the clutch is pressed

thing 3, legit... I've been working my timing to adjust to this car... the clutch engagement points are high in the clutch pedal stroke... that means that you have to get off the accelerator VERY early as you go for the clutch

I have no reason to rule out any of these... my solution is to replace the flywheel, work on my timing... but not sure i can do anything about SRM if it really is contributing... I like using it on the track, so not sure I want to defeat it

will know more once the single mass JWT flywheel is in... DDM is shipping to me late next week
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