It's been awhile, but I'm glad to be back.
I have a question about over boring my 1.6 SM.
The Block we have is too loose to use standard size pistons. So we are using the .010" overbore allowance. However i think the tolerance stack up in the Factory Service Manual could put my over the maximum bore size for the larger pistons.
FSM says Standard Piston Sizes range from 3.0690" - 3.0698" so adding 0.0098" (0.25mm) to that gives us 3.0788 - 3.0796 tolerance range for the overbore pistons. Is this correct? GCR says maximum piston diameter allowable is 3.0794.
The FSM also specifies that 0.0015" to 0.0020" piston to wall clearance. Is this on the radius or diameter? Does this mean that my Piston Diameter is 0.0020" less than the bore diameter?
Or is this the radial clearance from piston to wall, making the piston 0.0040" smaller than the bore?