Difference between 8ba and 59ab flywheel

HotRodmicky

HotRodmicky

Senior Member
Hi,
I have an aluminum 8ba flywheel that i want to use on my 59ab engine.
Is there an offset with the starter ring?
Beeing from Germany , swapping to correct 59ab is not easy .....

Is possible or WAY to much trouble?
 
Ol Ron's book gives a dimensional method of sorting them...essentially measuring distance from flange on one side to friction surface on the other. I've always had the right sort lying around so never worried about it.
I believe there is some offset, fractional, to ring gear. Actual interference problems I have heard of involve early wheel on late motor, the opposite of what you are wanting to do.
I don't see why the different width of the gear would matter.
Empirical approach...bolt it on and see if engine can be rotated. Add starter and see if it engages and disengages when fed electricity. I think the late ring gear will be slightly forward of early gear proper position.
 
Here's a pic of the difference! DD

222562
 
But note also the difference between gears is reduced a bit by deeper flange there. You need to do something like setting the flanges on a known size block and measuring thus to friction surface and to ring gear location so you can get truly comparable results. The practical questions are whether the gear winds up in the working travel of the starter drive and whether the thing clears the block and then whether main surface is not too far off...
I actually measured a bunch of this when I got hold of Ron's book years ago, but lost interest because I had a decent supply of properly matched flywheels. I blocked up the wheels on their crank flanges with sockets that were 1" long to make the arithmetic simple...
 
HotRodmicky, I know they are expensive, but save yourself a lot of grief and use a 49-53 Alum. flywheel.
 
Another option is a new steel flywheel from Centerforce that is much cheaper than aluminum, is about 10 lbs lighter than stock, come multi-drilled for Long/B&B/diaphragm and are available for both early and late flatheads.
 
Years ago I had a 58AB on the engine stand, I installed a 59 wheel and measured from the back of the block to the ring gear, and then I installed an 8BA wheel and the gear is about 3/8in. (I think), back further than the 59 wheel, the problem is the starter drive won't go back far enough to disengage the gear. NOW, if you going the other way around, putting a 59 wheel on an 8BA block you could put a spacer between the wheel and the crank. Walt
 
Did the same thing Walt and engine was already back in my 40 when I found out..... About as bad as putting a throw out fork in with a soft bolt instead of a hardend pin!
 
Starters interchange '32-53 on standard shift 221--255 enines. The difference must be made up in the location of starter mount so the starter drive movement range is in the right place.
 
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