5.09L Max Safe RPM
Safe is a relative word. It could mean safe from tossing a rod, or from overheating, or staving the oil pump over prolonged revving. I would say assuming its stock and in good shape, it wouldn't rev so high that it would blow itself up. Put a cam in it, open up the ports, reprogram the PCM without doing internal upgrades, you could likely blow it up with some effort.
depends on how much power you want and if you are willing to do the maintenance. 5.0L stock rpm is 6000rpm, lots of hot rodders take it up to 7000rpm to make more power and have a larger usable range, drag racers that are running motor only will go around 8000rpm. But I personally know of an engine & machine shop that made one scream up to 10,000rpm and make 758hp naturally aspirated, they used a bottom end girdle, hard-blok filler up to the bottom of the freeze plugs, titanium connecting rods, Ti push rods, Ti retainers and Ti intake valves, and a dry sump oiling system. Can't spill anymore details because then anyone could build one like it, lol.
I can't wait until I can scrounge up enough $ for a 302 powered car or truck, but i hope I was of some help with my previous post.
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