Engine/Trans/balancing?

[tmaddux911]

I currently have mid 70s 302 engine that is 50 oz balanced with a rebuilt C4 behind it. The engine has a bad vibration.

I found a mid 80s 302 bare block on my local classifieds already machined .030 over. I was looking into building a 347 stroker out of it.

My questions are:
1. Would I have 28oz balance the bare block?
2. Any issues using my 302?
3. Is an 80s block worth building?

 

[sykanr0ng]

A 1970s engine should have 28 ounce unless a 81 up crankshaft was used in a rebuild.
If you have a 50 ounce flexplate on a 28 ounce crankshaft that would vibrate badly.

Most if not all of the stroker builders want either a 28 ounce balance or a zero balance.

The 80s block is as good as most pre-roller blocks.

 

[tmaddux911]

A 1970s engine should have 28 ounce unless a 81 up crankshaft was used in a rebuild.
If you have a 50 ounce flexplate on a 28 ounce crankshaft that would vibrate badly.

Most if not all of the stroker builders want either a 28 ounce balance or a zero balance.

The 80s block is as good as most pre-roller blocks.

You are right, 28oz is what it is currently... I was trying to put my thoughts together while on the treadmill... haha

 

[needabronco]

.030 bore doesn't exactly mean anything. What pistons was it bored to? Piston clearence varies wether cast, hypereutectic, or forged pistons are to be used. Also if its a fresh bore or used block previously bored and now worn possibly needing remachined. Do some more homework.

Also the crankshaft determines the balance, not the block.

 

[tmaddux911]

.030 bore doesn't exactly mean anything. What pistons was it bored to? Piston clearence varies wether cast, hypereutectic, or forged pistons are to be used. Also if its a fresh bore or used block previously bored and now worn possibly needing remachined. Do some more homework.

Also the crankshaft determines the balance, not the block.

It’s a freshly bored and machined mid 80s block. All the listing says is .030 over, with cam bearings installed.