Balancing question

[Fkidd]

I hope I didn't screw up. I bought my Javelin in pieces and I have been buying the needed parts for 2 years. It is a 1970 360 4bbl and the flexplate I bought by mistake is for the later engines using a 727 instead of the Borg-Warner like I have. My problem is that I had the crank balanced with the newer style flexplate. Can anyone tell me how this will affect my balancing by using the Borg-Warner style flexplate or do I have to pull the motor again and have the crank rebalanced?

[fuzz401]

see if they can match balance the plate

[Fkidd]

I called the machine shop who did my balance and he started talking about whether they were both externally balanced and at this point with all the bumps in the learning process I just started to panic about having to start over. I won't get the correct flexplate for a few days but the machine shop said once he saw both plates he would know if he could do it. Like I said tho I started to panic.

[tufcj]

AMC V-8s are externally balanced. That means the flywheel/flexplate and harmonic balancer play a part in the balance.

A good machine shop should be able to match balance the B/W flexplate to the 727 flexplate. I'd say nothing to worry about.

Bob
tufcj

[Fkidd]

Great....thank you for the good news. It makes sense that even tho the trans changed the internals wouldn't. I can't wait to get my javvy going.

[cj5doc]

Do you have to have the pressure plate included in the balance procedure or can you just balance with the flywheel? Are pressure plates considered Zero balance?

[tufcj]

Clutch/pressure plate are 0 balanced from the factory. They should have no affect on engine balance. If it did, you'd have to re-balance every time you do a clutch job.

Bob
tufcj

[cj5doc]

Thats what I want to hear. My engine builder says they arent always zero balance and he recomends including it in the balancing process. He did tell me he could make a balance weight for the flywheel to zero balance it. He said this would allow for any later change of pressure plate to easily balance it with the flywheel. Seems to much form.... maybe if you are building a drag engine.