Alrighty well to get right to the point, car idles well and fires immediately but once driving after about 2200 rpms the car begins to shake (pretty good) and struggle almost. Feels like its in the engine that why i feel its a mis, but a buddy is telling me it might be a transmission / trans mount situation. would a bad mount cause this vibration?? And the car doesn't really feel like it has a bad mis whenever i rev it at idle, but when i'm moving you can definately tell somethings up. Any opinions on how to diagnose this prob would be greatly appreciated thanks.

oh car is a 94 trans am w/ a 6 speed. new opti, recent plugs