HandmeDown xf 0 Posted December 12, 2020 g'day to yal new to the sight been browsing around and like wot i see, thought i would stay awhile and ask a couple of dumb questions hope that does not annoyed anyone . i have been trying my hand at rebuilding an xf ute 250 crossflow going well for first attempt i have got up to clocking the rings on to the piston before attempt pushing the little buggers back into the block ,there be the problem though i have read the Gregory,s holey scripture only to just get even more confused as to wot points where ,it may as well be written in sand script or o ancient Hebru becouse it just does not make any sense to me at all. i Have done the usual thing and stuffed the internet only to come up with 50 more different ways of doing things to end up even more baffled than i am now ..... so just wonder if someone could demystify this strange and yet baffling science about which ring gap goes where as to the correct spec for this motor and more to the point if some one could lead me down the right path with this that a blind man may follow.....thanks Bretto Share this post Link to post Share on other sites
slydog 7,873 Posted December 12, 2020 So first thing to know is the rings rotate in the bores as they go up and and down so don't stress too much. But for the argument I set the oil rings 180 apart from each other and find a spot on the piston im happy with. Then the 2nd ring goe's as far away as you can get it from the "top oil ring" gap. Then the top ring is 180 opposite the 2nd ring gap. But the rings still rotate in the bores at there own rate anyway so don't be too concerned. 3 2redrovers, deankxf and Slow250XC reacted to this Share this post Link to post Share on other sites
hendrixhc 10,918 Posted December 12, 2020 Welcome aboard Bud! What Sly said ^^^^^ 2 deankxf and slydog reacted to this Share this post Link to post Share on other sites
deankxf 20,233 Posted December 12, 2020 welcome aboard, first i've heard they rotate in the bore/on the piston.. interesting indeed. 1 slydog reacted to this Share this post Link to post Share on other sites
slydog 7,873 Posted December 12, 2020 8 hours ago, deankdx said: welcome aboard, first i've heard they rotate in the bore/on the piston.. interesting indeed. Pushrods and lifters (if flat tappet) do too. Along with valve springs if you watch a spintron in action. 1 deankxf reacted to this Share this post Link to post Share on other sites
HandmeDown xf 0 Posted December 13, 2020 thanks guys for the welcome .slydog your input thanks heaps, as for the piston rings i have read that all the rings move at the same rate around the piston as they go up and down so clocking them against each other is more important than where they are inserted at that time of build ,so i guess that's really wot i am taking away from your answer .. moveing down the line a tad to another question i have " gapping the rings" ..., ' I bought a set of silv-o-light pistons which from manufacture saying they are HYPEREUTETIC pistons and that the top ring gap should be 40 % larger than recomended gap size of 0.25 - 0.50 buy the book.....so if i am getting this right 0.25 as the minimum plus 40% = 0.35 gap for the top ring ??? (I have read somewhere that the 2nd ring gap should be grater than the first one to stop fluttering of the piston) but the piston manufacture says 2nd ring as per book spec not shore wot the second ring gap should be? i would gues at minimum 0.25 ??? ps useing Hastings rings 4409 030 Share this post Link to post Share on other sites
slydog 7,873 Posted December 13, 2020 Sooooooo...tighter you set em longer they last usually but there is a limit to both sides of that comment. Some work on x.007 of bore. I actually set my Wiseco's at 15th top and 2nd 17th 8 years ago. After much of that time NA and 8200rpm and later a P1SC Procharger I pulled the bottom end down to ready for a freshen up and found there at 26 and 28th respectively. My turbo combo will be set up the same with 26th top 28th 2nd. So I never go crazy on ring gap and TBH 20-22th and 22-24th on a stockish engine set with 3or 4th piston bore clearance is heaps IMO. Share this post Link to post Share on other sites