Safe max RPM for bone stock 5.9 magnum

Brooks James said
Stock cam and valve Springs are done at 5000

My stock long block 5.9 is done by 4500, can’t miss it.

Dan the man said
I find it hard to believe that a stock 360 will run 12's, even with a mild cam and only casting clean up.

Start re thinking on how things can be done. The 5.9 has a 9.0-1 ratio stock. While a slight light on squeeze, it’s not bad and will work with mild cams. After that, it’s how well you 1; tune the engine & distributor, 2: get the power to the ground, 3: maximize the gearing to make max power at the finish line stripe. You’ll want to trip the lights where max power is being made or very slightly there after.

Just remember your camshaft has to fill the heads as much as possible, close the valves at the optimal time and then the ignition ignite it off.