if u have a 327 and wanted to change to a 383 with a 350 block u would have to change the motor mounts right? i was reading in CHP that if u had a 327 and wanted to drop in a 350 u would need to change the mounts or you would get a bad vibration, what kind of mounts do you change to for a 327 to 350? and a 327 to a 383?

Please go over to David Pozzi's great site and read up on this.

pdq67

They're all the same unless you're swapping generaton-to-generation. All small-blocks had the same exterior dimensions. Use what came with the car.