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Raynoslo!

At .070" overbore, the cylinders' spigots will distort as much as three thou inward, and three thou outward, from the basenut stress alone.

If your bore and hone was not performed with stress plates, and the cylinders installed to the same torque, you set yourself up.

When fitted while stressed, 74" cylinders can be taken as large as .100" over.

.....Cotten
 

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Cotton.....

Who makes those pistons in a .100 over for the 74" 3-31/32 stroke

Are they a special order deal...????

Got a few sets that have been maxed out ...
Like to get them back on line..Without popping sleeves in them..
Dragstews!

I always got them from Dixie, and they were identical to the Superior pistons sold by major distributors. ("JCC" or whatever.)
Ross and other companies will make anything you want.

Every cylinder must be carefully inspected, of course, as previous pokes from boremeisters might not have been as masterfull as hoped, an the bore may no longer be n the center of the casting core.

Our first requirement for an educated assessment is to find a way to measure the remaining casting thickness.
I removed the top spring from a common caliper so that the thumbscrew could be reversed, thereby making it openable to clear the baseflange, after setting to a feel for the thinnest spot.
Re-closed, the gap can be measured with a feelergauges, or a dial caliper if large enough. (First attachment.)

The thinnest spots in the cylinder wall are in the milled cuttaways for basenut clearance. I probe the radius of the cut to determine the minimal point, and set the caliper. (Second attachment.)

With 74" cylinders at .100"-Over, and 61" cylinders at .155" over, I found .070" remaining, and have adopted this figure as the minimum safe thickness.

This does allow a margin of safety, as I have an oriental cylinder that ran at what appears to be about .005" wall.
I put my fingernail through it!

(Third attachment.)

....Cotten
 

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