Update on my hi-miler Z project - ZR-1 Net Registry Forums

VetteMed · 03-06-2012

DId some highway driving today, and noticed that there's a fairly significant vibration at around 75 mph and up. Seems to become more intense with increasing road speed. Does not seem rpm dependent, as I do not notice it at lower road speeds in lower gears. Depressing the clutch causes a significant reduction in the vibration. I should note, that this issue was present with the old motor as well, so I don't think it's related to the motor, UNLESS it's related to the rough idle, which might be injector related?

I'm going to start by having the wheels road-force balanced, and I'll rotate the driveshaft 180 degrees. After that I suppose I'll send the driveshaft/yoke out for balancing.

I am hoping I don't have to remove the pressure plate and rotate it 120 degrees and reinstall; there was a paint dot on the pressure plate but no dot on the NOS dual mass flywheel, so I didn't have any particular reference for choosing position.

03-06-2012	#10
VetteMed Join Date: Mar 2009 Location: Orlando, FL Posts: 1,816	Re: Update on my hi-miler Z project DId some highway driving today, and noticed that there's a fairly significant vibration at around 75 mph and up. Seems to become more intense with increasing road speed. Does not seem rpm dependent, as I do not notice it at lower road speeds in lower gears. Depressing the clutch causes a significant reduction in the vibration. I should note, that this issue was present with the old motor as well, so I don't think it's related to the motor, UNLESS it's related to the rough idle, which might be injector related? I'm going to start by having the wheels road-force balanced, and I'll rotate the driveshaft 180 degrees. After that I suppose I'll send the driveshaft/yoke out for balancing. I am hoping I don't have to remove the pressure plate and rotate it 120 degrees and reinstall; there was a paint dot on the pressure plate but no dot on the NOS dual mass flywheel, so I didn't have any particular reference for choosing position. Last edited by VetteMed; 03-06-2012 at 03:40 PM.