ok heres the situation: i bought this car from a buddy who had just installed a cam in the 340 with x-heads, i finally got the car restored and now it wont rev past 5000 rpms without losing power and breaking up. i got a few sugestions from members on this forum that the valve springs might be old. so i asked my buddy what valve springs are in the heads and he said they are new, but they are stock!. so my uestion is what size cam are stock x-head springs good for? the cam s a lunati voodoo
.494in .513exh.
duration .050 226in. 234 exh.
it also has 1.6 rockers