Highest LIft cam with 68 340 with stock intake and carb

first of all, the spring heights are too short for that cam, you will have coil bind big time!!!! secondly, piston to valve will probably hit. there is not much room with stock pistons for big cams. also, to install a roller, the oil passage on right side has to have tube installed for oiling, about most lift with stock springs is .500 lift, need to go different route. BTW, the stock intake and carb will not hold it back. a 71 340 duster, in D/SA, ran 9.92 @ 130 mph. has stock intake and carb. imagine that !!!


I agree with all of this.
If you are very careful you can get a spring to take .600 net lift with SFT lifters. I'd have to go and look to see if I can find a spring that would take a roller lobe at that short installed height.