Re: Arias pistons question...
Some of the older "special things" included "press fit rings"!! The rings grooves were super tight, and to install the top rings you had to heat the piston to install the rings. Otherwise, the ring would not fit in the groove. This feature would make pistons so equipped useless as street motor pistons.
Make sure the pistons are not of this type. Get a piston ring that should fit and see if you can slide it in the groove. If they were truely made in the 80's, I believe the "Press Fit" style was out of vogue by then.
Make sure the wrist pin isn't up into the oil groove.
A lot of the older piston skirts had a slick finnish that did hold oil very well. If the pistons are made like that, they will benefit from glass beading the thrust surfaces.
406 SB, Original Bill Thomas '63 Rochester FI
AFR 210, Lunati 501C2LUN, 255/263@.050", .628"
10:1, TH400, 3.31's, 4400 SS
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