just did a refresh on a small port 4ag i put in big port cams and adjusted the valves to spec . whats the best running in time for these 1500km's? does somebody hAVE A PROVEN GUIDE ? CHEERS FOR HELP; COMPS ARE ABOVE 200PSI WHICH IS GOOD
Have you put in new pistons/rings? Overbore/rehone? Or is it just the cams/headwork that was done? New valve springs? Wearing in rings vs wearing in cams are 2 very different processes.
Rings and bearings, a low km head with biger cams.I had to reshim to suit the big port cams;Im on the lines of keeping it under 3000rpm for 500km's with minium load where possibe; changing the oil and filter every 500km untill 2500.After every 500 km's my revs increase by 500-1000 rpm any thoughts ? i used ACL chr'molly rings ACL bearings (watch out though my 1st set of mains had a crack in them !!!!so i had to wait another week for them Thats y its taken 2 weeks to do the lot has cost aprox $350 i made up new gaskets where i could. Originally i done a h/g but i thought id do the bottom end to Lucky i did, it ended up chewing no2 bigend on the piston side; too much load /rpm and poss timing, no4 mains just started to go but clearence is still within specs
I am more inclined to go for a hard engine break but i have large cams to deal with as well. Generally to wear in cams you leave the engine to idle for about 1/2 hour or so. But, idling for that long is the WORST thing you could do for the rings.
Either way... don't baby the engine too much. You'll need to put some load through the engine to get the rings to bed properly. Dont stick it in 5th and try to pull up a hill with your foot to the floor though... that's the wrong kind of load. The engine needs to rev out.
I wore in a new engine too soft before i knew anything much about engines a few years back and that car now has a slight piston rattle at very low rpm.
Fri, 18 November 2005 08:15
Thats y its taken 2 weeks to do