Replacing Piston Rings

[ahh 33 s2]

hey all i am wanting to freshen up an rb 30 block. with bearings and rings. i am not sure if it is ok to just put the new rings in without doing anything to the bore itself. i dont want to have to buy new over size pistons.

will the rings seal properly if i just put them straight in.

thanks

dan

[Swiper the Fox]

hey all i am wanting to freshen up an rb 30 block. with bearings and rings. i am not sure if it is ok to just put the new rings in without doing anything to the bore itself. i dont want to have to buy new over size pistons.

will the rings seal properly if i just put them straight in.

thanks

dan

no it will need a hone, a glazed worn bore will not allow the rings to properly bed in. Depending on the wear you may be lucky and just get away with a honing the cylinders. If too worn an excessive skirt to bore clearance will make the engine "breathe" too hard and also ring end gaps may be excessive.

[ahh 33 s2]

thanks dirtgarage, that is what i thought. and obviously if there is excessive wear to the bore it will need to be bored to over size.

[Swiper the Fox]

thanks dirtgarage, that is what i thought. and obviously if there is excessive wear to the bore it will need to be bored to over size.

If it has cast pistons you may be able to get away with a set of forged pistons and a hone. Forgies need a greater skirt to bore clearance so depending on the amount of wear you might not need to bore oversize.

[SKiT_R31]

most rb30's keep great condition even with high kilometers, for examply my 200+ thou km block still had the original honing marks, if yours is similar and you can see them just a hone should be fine, i know of alot of people who have just honed the bores and returned perfect compression with no blow by.