Lightweight flywheels can tend to cause misfire issues, the problem is the engine accels and decels faster then the ecu can proccess the cam/crank sensor signals this leads to a cel for random misfires. i had this problem running a act strip flywheel, and a lightweight crank pulley.
also i hear bad things about running both due to less dampening and causing lower end bearing damage.
Second all of that- the reduced dampening results in more overall noise/vibration which can trigger sensors- also the drivability is usually negatively affected, bogging at launch, stalling easy, blah blah blah... all a pain if you don't really feel like 'compensating' for it, i.e., revving the crap out of the motor, praying the clutch grabs before it burns out, praying that your drivetrain holds together for the shock...
And the lower end bearings are also negatively affected- you can (attempt to) compensate for it by getting closer tolerances and having bearings oversized/machined/whatnot to tighten up the tolerances, but you hopefully know exactly what you doing in terms of clearances versus oil viscosity (I remember Dom having a handy dandy write-up on oil viscosities vs. bearings/clearances somewhere here)... blah blah blah. It's extra vibration from reduced dampening that the assembly was never designed to tolerate.
Eh, it's something I like to complain about in general though- you're making it do something it wasn't designed to; it's gonna wear out/break faster than 'normal'. So, you can upgrade parts/maintain parts/whatnot to prevent it from happening, or just suck it up and have spares when it does go bad. That being said, I've just learned to keep as many spares as I can afford to... granted it's a honda, so spares are cheap.
Sorry if that comes across as negative sounding, bad day at work.
Topic: light weight crank pulley vs. light weight flywheel? (Read 3449 times)