What cam to use in 340

a solid roller is a complete waste of money on iron heads . the entire point of a solid roller is to be able to make a very aggressive profile that opens the valves extremely quickly and unless you have heads that flow a ton of air, you will not be able to optimize the benefits of one . the key to hp is in air flow . if you don't mind adjusting valves and having a noisy engine, you could run a flat tappet solid cam and save yourself around $400.00 . if the heads are not ported, you might be able to find someone that will do some basic bowl blending and valve guide profiling for around $700.00 . this will include regrinding the valves and seats . they can check the guides at the same time . if the springs are stock you will need new springs for around $120.00.

if you like to rev the engine and dont already have an intake, i would run an air gap instead of an rpm.

if you use a solid flat tappet cam, i would use the howards cams lifters with the oil hole in the bottom.
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