Ok, This is really getting interesting...I emailed the Engine Builder today and told him of the "thoughts" here on A Body and what I did ... here is his
response: By the way...When he installed the new motor, he installed brand new TTI ceramic coated Headers and the motor was installed using brand new Schumacher motor mounts ordered directly through Rick Schumacher... ok here we go......
John,
i did look at the driveshaft. we had the car up on four jackstands and ran the car through the gears. we couldn't see any vibration or anything weird with the driveshaft. the only think i noticed was that the pinion angle looks like it's maybe 9 or 10 degrees down. that might contribute to the problem.
i'm not sure what running through the gears without the driveshaft would accomplish. the flexplate and torque convertor turn any time the engine is running. there isn't any vibration if the engine is rev'd up in neutral, so that would eliminate any type of flexplate issue.
the torque convertor was bought specifically for your combination and was ordered as neutral balanced. normally the convertor for that car would have weights on them.
here is a link to the shop that shortened the driveshaft. http://www.yellowpages.com/lake-worth-fl/mip/drive-shaft-power-inc-2905847?lid=2905847
i still believe that there is contact between the headers and the body of the car when under load, but i have no way to visually see something like that. as you know, almost anywhere you look around those headers is close to touching something, somewhere. i don't know how much play is in those conversion mounts, or in other words, how much they let the engine move around under load.
