My friend gave me his crank out of his 5.0 84 1/2 Gt 350.I put the stock flexplate on the motor that came off of the old motor.Do I need to get the flexplate from a 84?Its a 68 block.The crank is all i used.
If you used the 68 flexplate then it is the wrong imbalance. The 84 engine uses a 50 oz imbalance and the early engines used ~28 oz. You need to get the one that macthes the crank...so you need a 50 oz imbalance for a small bellhousing (157 tooth) C-4 as I am assuming you have an automatic.