your thoughts,
450 hp gm crate motors, with upgraded crane valve train,stud girdles, merlin heads ported with inconel and sever duty valves, dart intake, etc..
what is safe as max rpm??

i have been told everything from 4900- 5900 rpm
your thoughts please....

about 90hrs total on motors
about 10 hrs on top end since all upgrades,

thanks for input..
gonna take a poll
5000
5200
5400
5600
or anyhing inbetween

I have GM 502s and they run strong at 5200. I'm sure they will handle more by I won't push it. 5000 is safe.

got 5300-5500
got 5200
so far
i like the #s i see.
what is the weak link at high rpm in these.

5000 and your safe for a long time.5300 max and they will live. R.B.

5900 too high, unless you like rebuilding all the time. 5400 is as high as I go on my blower motors, and then only for short time periods. 5000 is great if your boat planes good with props on it to limit RPMs that low.

The bottom end of a 502 Mag should turn 6500 no problem. I ran my 502 in a previos boat 5600 with no problems. It was a solid roller motor though. Valve train will be your weak link..

The bottom end will take 6000 RPM all day but it does wear it out quicker. The max RPM will depend on how well your engine breathes. More in and out = more RPM.
I ran mine a whole year at 5900 RPM untill I bought new props. I am proping mine for 5400 RPM.

good info thanks
830 holley gill exhaust in fast out fas but nevr fast enough...