I've been all over the various forums and most seem to align with the minimum or should I say optimal ring gap for 96mm pistons/cylinders. My 2056 build is for normal street use.
Just received a new set of AA performance biral 96 mm pistons/cylinders. No documentation came with them but the vendor recommended the guidelines below. Rings are suppose to be Hastings.
Top comp ring optimal gap should be .0045"/inch of dia so
.0045 x 3.77953" (96mm) = .017"
2nd comp ring optimal gap is .0040/inch if dia so
.0045 x 3.77953 = .015
These guidelines seem to follow other published tables, but the Hastings table guideline is .0030/in of dia which would be a minimum of .014"
My measured top ring gaps are 2 at .018 and 2 at .019
measure 2nd rings are 2 at .016 and 2 at .017
So we seem to be in alignment.
Factory specs for 2L motors(94mm) have minimum of .014" and .012" respectively which also seems to support the above 96mm numbers
So question for the group, it seems like we are right where we should be, but what have others done based on experience. Several past posts say to open up the top gap to .022. So what is correct for these pistons?
Also of more concern to us is the measured side clearance for the new AA pistons is very tight for the compression rings. All are measuring a tight .0015". Vendor claims this is ok, but seem tight when factory 94mm specs say side clearance should be minimum of .0024"??
Any thoughts before we put this thing together.
Thanks
jjs3rd914