Help on rebuilding a 73 340

isn't a 73-340
external balanced?
if you are swapping out the 318
hate to see you finish the project
then car has the shakes>vibration

Yes, it is. Been there, done that. Bought a 73 340 out of a wrecked Challenger back in 80's. Rebuilt it using early pistons and a Racer Brown camshaft and springs. Stock intake and manifolds with a stock TQ carb. It ran real well with a four speed and 3.23's, once I got the vibration problem figured out... :banghead: