I have NO idea why these cars idle so rough, my biggest complaint with it. I have a feeling the majority is in the torque tube bushings/steering rack on the driver side mount. I found this little experiment made my car about 30-40% smoother while idling. Try it if you like, but I still need to do more. My SRT8 idles so smooth, my KB Cobra idled smooth and why can my C6 idle smooth?

Anyway, I tried this while I was witing for Chuck to get my ECM finished.

I went to Homedepot and grabbed some ac insulation.



I then pulled the exhaust, which wasnt necessary for this but I wanted to see every inch where any interference was possible between the drivetrain/frame/body that could cause vibration. Nothing else stood out though other than the fact that the rack only has one bushing on the passenger side, the driver side is alluminum to alluminum....Hmmm.

Removed the 1 bolt on both sides holding the motor mounts in.




I then placed a wood block onto the oil pan/bellhousing and jacked the car and the engine lifted right off the mounts. No fuss.


Then I removed the bottom bolts (1 per side) and pulled the mounts, though not necessary, I wanted to see and feel the mounts. I cut a square section of the insulation and placed it on the bottom of the mount where it contacts the alluminum frame. Believe me, it compresses 95%.



Then I put the mounts back in the car, they only go in one way. I also added a square of the insulation on top of the alluminum shield (top of mount) where the alluminum bracket comes off the engine. I forgot to get a pic of that, this was all an experiment.

Then I lowered the engine back down, very simple.




I really torqued the bolts to compress the foam and I didnt run into any problems.

This made it about 30-40% smoother, even my buddy who has only been in the car twice, noticed a difference.

 

I take it you feel less vibration, but have you any idea of how to smooth out the idle? Mine is VERY rough, even "staggering" occasionally, until fully warmed up.

 

This is just speculation since I don't have a Corvette yet... but cleaning the MAF sensor makes a world of difference on most other cars.

You can pick up the cleaner at any Autozone/Pep Boys etc. It should be near the brake cleaner and is labeled as electronics cleaner. It made the idle on my M3 smooth out by easily 80%.

P.S. I'm in Tucson also.