Crankshaft imbalance

Topic: Crankshaft imbalance (Read 1686 times) previous topic - next topic

Crankshaft imbalance

September 25, 2005, 09:15:11 PM

I have finally gotten a used 302 home and torn down. This motor is supposed to have a boss 302 race crank in it. The motor was to have been balance also. There are no holes drilled in the counter weigh of the crank. It looks like some one has ground on the bottom of the connecting rods to balance the pistion and rod combo. Is there a way to tell what balancer I need to use? I'm putting this in my 87 cougar that I have converted to 5speed. I have used the flywheel, clutch, and tranny from a fox body mustang. My current motor uses the 50oz balancer. Attached is a couple pictures of the crank and a picture of the bottom of a couple rods. Please let me know what you think.

Re: Crankshaft imbalance

Reply #1 – September 25, 2005, 10:34:44 PM

That is a nice looking crank... All the Boss 302 used a 28oz ballance, so if it hasn't been drilled I'd say thats what it is. Is there any part/casting numbers on it or the rods??

Re: Crankshaft imbalance

Reply #2 – September 26, 2005, 08:42:28 PM

Attached is a picture of the crank casting number. I'm not able to make them out. The rods have casting number of C80E-AAQ51. The rod caps for cyl. 2,3,6, & 8 have D10E AA 240 S. Cyl. 4, 5, & 7 have D10E AA 236 S. Cyl. 1 has D10E AA 237. The pistons all have E7ZE-6110-CA. I believe the pistons are factory forged made by TRW. Do you think that a good machine shop can tell what balancer I need?

Re: Crankshaft imbalance

Reply #3 – September 26, 2005, 09:54:09 PM

The E7 pistons would be for a 50oz ballance, the rods could be either. I'm betting its a 50oz, but a machine shop can tell for sure. You'll need to take them all the parts with bearings, rings etc.

Re: Crankshaft imbalance

Reply #4 – September 29, 2005, 11:24:59 AM

thats not a factory crank

it looks like a light weight 302 1 piece rear main crank

50.oz balance 1982 up

before that they were 28 oz and the cranks had more counter weigts to them

a "Boss 302" crank will not fit in a 302/winsor style block

The "Boss 302" is more of a cleavland looking crank