Just completed 3.6 swap into 986 and have vibration.

[Smallblock454]

Hi,

i'm pretty shure the problem is not the engine mount or the mounting height. As far as i know the flywheels are balanced different, because internal masses are different and the 3.6 blocks of 996 engines differ from 3.2 986 blocks.

Another can cause of vibration/drone at this rpm range can be caused by the exhaust. But from what you've said i would say it's a balancing problem.

Regards
Markus