Vibration over 5k
 

Ever since i have owned my car it has had tons of vibration above 5k rpms. i know it needs a new tranny mount bushing so that is most likely part of the problem and im going to fix it as soon as i get the money. but i think doubt that is the only problem. any ideas? Its a 91 n/a convertible with a manual conversion.

driveshaft u-joints and/or driveshaft angles

No.

Engine mounts/Tranny Mounts most likely...

If it were a driveshaft u-joint, it would be speed/load dependant, not RPM dependant.

hmmm, good point. then he may want to check the water pump and alternator for shaft play... and if the motor is old and tired it could very well be wornout rotor bearings or stationary bearings... also could be an out of balance clutch/flywheel

Well i know the water pump and alternator are good cuz i just replaced the water pump myself including all the belts, spark plugs, spark plug wires, all fluids but i double check the shaft play tomorrow. I doubt its the motor cuz it is running like a top and just wants to keep climbing even though its vibrating like crazy above 5k.

An out of balance clutch/flywheel is definitely a possibility cuz I'm not the one who did the tranny swap. ill replace the tranny mount bushing and see if that helps. ill keep you guys posted.

It's probably a broken engine-mount.