I got a set of pistons with rings std bore said 10:1 forged do I need to file fit rings or they set. I build Detroit diesels and when you get a set the rings and pistons sleeves. the rings are preset. I have cyl honed guess I should check ring gap
I left my Crystal ball home today so can you please post up what cid motor it is your question pertains too, as ring availablity may be limited, Lol! In general some rings can be considered a drop in, this can be for std Bores and common oversized bors. But note that this always takes into consideration some leeway even with a dead on perfect size stock Bore. If you are working with even a low milage stock Bore with some ware I would go for a .005" oversize stock Bore set of rings and then file fit them with the needed proper tools to do such, as it's always worth doing it thus way in terms of power and keeping the oil free from Bearing waring carbon build up and crankcase vapors blasting oil out of your breather caps! Keep in mind that since we are working with a cylinder , so r every .001" of ware above a stock Bore size will make for a ring gap increase of over .003" ! Of course you could always just lube up the upper part of any finished bore, load a top compression ring in and square it up with a piston top and then confirm what you have for a ring gap as is. If your golden gap wise after this check out then be sure to use a soap stone or 220 grit sand paper to break over all the edges of the top & second compression ring along with the oil ring rails such that there is no sharp edges to scratch the cylinder walls and make for added friction, and also so that these edeges to not enlarge the ring grooves they load into as they spin around the piston as the motor runs.