Thread: Getting into the 12's

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what you have going on is very common with a big block have see this from 500 lift to 800 lift and had to fix many.this is not to big of a deal on the big cid engine the the rods will hit the cam to that is engine building the pistons on a big block will hit all of the time intake side i have used them pistons you have in 6 or so builds and they will not take much cam so they will hit if the valves are hanging down you may want to try moving the cam retard 4 and try that you will not see much but you would be better cutting the pistons .and put the cam where it should go i would not look at a custom cam for this problem if the intake valves are to low you will have a lot of promblems if the pistons do not have a big valve relief and them do not i have cut them .060to get 710 lift roller cams to fit with 268 @ .050 on 110 lsa you need to make sure you do not cut in the top ring land or get to close with the nos you will burn the piston where it has been fly cut so maybe both move the cam and cut the pistons you do not want to cut down to or past .060 if you are using nos if you do not have to cut that much say .030 with the cam where it should be you will be ok i have runned many down around .060 with roller cams with big springs BUT you need to check all the holes and would say on a hyd cam you could at by at to 080 but like i said you nee to know all the holes are that or more not all of the valve fly cut hits the piston sometimes you can tape the engine of and use a psa sanding disc and sand the deep part of the stock fly cut BUT you have to make srue no junk get in the bore or engine or you can rent a cutter from isky or make one from a old intake valve it will work you need to use a head like yours or you head to hold the valve with some tool steel welded on the face or have it cut in the valve face with teeth this is low tech but has been done many times with out taking down the bottom end do not ask me how i knowoh grind a hex where the keepers would go on the valve stem so the drill can hang on with out digging in the valve stem and screwing up the guildes in the heads