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986Jim · 04-02-2006, 07:22 AM

One other odd thing a lightweight flywheel does is allows the car to rev quicker but also allows it to decelerate the RPM out of load faster.What happens is sort of annoying depending on your driving habbits. It never bothered me but did other people..

My talon has a Competition Clutch and ACT lightweight flywheel 12lbs vs. 20lbs stock. So thats 8 less lbs from the flywheel. I also eliminated the balance shafts (imbalance shafts also as they are known) and run hollow Comp Cams 101200 highlift cam shafts in the car.. The balance shafts were 6lbs and the cams shaved 2 lbs. So over all that was 16lbs of rotating mass off the engine.

When I drove the car coming towards a stop sign, naturally I always leave the car in gear and just let it rpm down towards the stop sign then push the clutch in when the RPM is near 1000rpm even if it's in say 3rd gear and im going slow. I'll just wait until the rpm is low then dis engage the clutch. What most people do is see the stop sign way ahead and push the clutch in right away and also break.

What happens if you push the clutch in from say 4000rpm and it falls is the light weight flywheel allows the RPM to fall faster than the ECU is ready for and the car will stall before the ecu will compensate and hold the rpm steady .

When a buddy was driving my talon he kept stalling the car coming upto lights and stop signs because he insisted on pushing the clutch in at 3000-4000rpm really early while breaking instead of just breaking and leaving the clutch engaged. It caused the car to keep stalling because the RPM decelerate so fast because of the light weight.

This is possible and quite likely on the boxster as well depending on how much weight is saved from the light weight flywheel. From a performance standpoint it's totally worth it espically on a NA car (turbo the effects are less) but if you can't handle a trade off like that then think again. Maybe somebody with a lightweight flywheel on their boxster can chime in and let us know if this is an issue or not.

I know on the Talon/Eclipse, Supra, and most honda's they have this problem, it's not car specific but light weight flywheel specific.

04-02-2006, 07:22 AM	#4
986Jim Registered User Join Date: Feb 2006 Location: Toronto Ontario Posts: 291	One other odd thing a lightweight flywheel does is allows the car to rev quicker but also allows it to decelerate the RPM out of load faster.What happens is sort of annoying depending on your driving habbits. It never bothered me but did other people.. My talon has a Competition Clutch and ACT lightweight flywheel 12lbs vs. 20lbs stock. So thats 8 less lbs from the flywheel. I also eliminated the balance shafts (imbalance shafts also as they are known) and run hollow Comp Cams 101200 highlift cam shafts in the car.. The balance shafts were 6lbs and the cams shaved 2 lbs. So over all that was 16lbs of rotating mass off the engine. When I drove the car coming towards a stop sign, naturally I always leave the car in gear and just let it rpm down towards the stop sign then push the clutch in when the RPM is near 1000rpm even if it's in say 3rd gear and im going slow. I'll just wait until the rpm is low then dis engage the clutch. What most people do is see the stop sign way ahead and push the clutch in right away and also break. What happens if you push the clutch in from say 4000rpm and it falls is the light weight flywheel allows the RPM to fall faster than the ECU is ready for and the car will stall before the ecu will compensate and hold the rpm steady . When a buddy was driving my talon he kept stalling the car coming upto lights and stop signs because he insisted on pushing the clutch in at 3000-4000rpm really early while breaking instead of just breaking and leaving the clutch engaged. It caused the car to keep stalling because the RPM decelerate so fast because of the light weight. This is possible and quite likely on the boxster as well depending on how much weight is saved from the light weight flywheel. From a performance standpoint it's totally worth it espically on a NA car (turbo the effects are less) but if you can't handle a trade off like that then think again. Maybe somebody with a lightweight flywheel on their boxster can chime in and let us know if this is an issue or not. I know on the Talon/Eclipse, Supra, and most honda's they have this problem, it's not car specific but light weight flywheel specific.