snikers01

I have J302 heads that I have been running with a b cam since the 90's. Time for a change, pulled motor mild port job on Gt40 intake and heads. Installed Trick flow stage 1 cam straight up an it is hitting the piston. Pistions are wiesco .30 over. same pistons i had with the b cam. Do I need to advance the cam?

mjr46

what size valves are in the j302 heads? are these the original alan root j302's or the svo j302's???? some had 2.02's iirc but most were cast with 1.94's.......also is it hitting radial or vertically??

snikers01

I thought they were 202's they are svo. Hitting the valve relief and edge of relief see photo

mjr46

how are you checking for ptv?? are you using a converted lifter or solid lifter??........with aftermarket pistons and afr 185 heads I've used way larger cams and not had an issue?? are those pistons for inline valve heads or twisted wedge heads??

tinman

Time to start playing with advance/retard. You should be able to get .100 clearance on both valves. Use the rings that you are going to use in the engine to check with, not light springs. I would use a welded lifter for checking.....

snikers01

Note to self don't install cam at 9pm. Put cam in at wrong timing mark. All is good now. thanks for the reply's.