i bought a 85 camaro from my buddy with a automatic. i put in the t56 trans because the automatic was bad. So i never got to drive it with the auto, now i have a very bad vibration at high rpm and high speeds. The engine is a 305 gm good wrench, not sure if this is a internal or external balance engine. im hoping this is just a bad drive shaft, but it looks fine. my tires are bad, but i dont think it could cause vibration like this. any help or ideas would be great

 

ok i found the sales receipts for the engine, it looks like its internal balance. gm part number 12531687.

http://www.sdparts.com/product/12531...ateEngine.aspx

 

i have had some crapo tires shake like crazy, also the steel driveshafts commonly have troubles in our cars, getting it rebalanced wouldnt hurt

 

my tire are very bad, but ive never seen tires cause vibration like this. i can feel alot of vibration from the shifter. im goin to look into getting new tires anyways. i will try to get it balanced or another used one in a week or so.

 

here is the thing on the used one, so many steels had trouble you may just get another junker, if you got a drivetrain shop local its prob worth it to have them balance it, if you aint got one local try replaceing the u joints that may help some

but i have rode it a fully restored 3rd with an alum drive shaft and it hade some vibration in it, i dont think out cars will ever be smooth as a new one at 75+ but i may be wrong, i know they sure aint as smooth as the honda

 

What are u running for a cross member , also look behind your harmonic balancer see if there is a weight in it . With that motor you would need a special 2-piece flywheel .Witch flywheel do you have . Don't spend your money on tiers yet .