The short version of the long story is that I rebuilt a 350 about 2 years ago. 1500 miles later I pulled the motor out after the car was totaled, the motor sat until the end of this summer when I dropped it in the new ride.

When I get the revs up to 3500 or so I get this vibration that 'seems' to come from the center of the car, the transmission tunnel somplace. This happens at pretty much any throttle position or gear. I have subframe connectors that are pretty close to the top of the exhaust just uder the passenger seat. I doubt the exhaust is hitting the subframe connectors hard enough to cause this, I also have a piece of that high temp silicone tubing stuffed in between the two knowing it could set off my knock sensor. My motor mounts looked OK, tranny and torgue arm bushings are energy suspension parts. When I first felt it I thought wheel spin or axle hop.

I know this is a shot in the dark asking online... but you guys know all that wacky stuff I would overlook. Thanks for the help.