What is the max rpm on a stock 87 330 merc. I know the sticker says about 4400, but I didnt know if it could take more.
Also it has 425 hours on it
Thanks Chris

A stock 454/330hp, 21 years old with 425 hrs.

Better stick with 4400 or maybe 4200.

you best do what whatabout1 suggested, you push that motor to hard you will be paddleing.

I think the factory rated that motor for a max of 4600 rpm

dont push it too far. from my experience with 330's they do not like to be pushed past 4800rpms and that was on a brand new motor. 21 years old i would give her a break and keep it under 4400rpm. other wise a 330hp is a great motor and will give tons of reliable fun if not rev'd up high. good luck

They sing at 5000. In '88 all the Velocitys new were propped to turn 5k. I had many customers and friends with them. Just run and burn the belts off them. If it turned 5k you cruise at 4200. I know boats that never run any slower if off idle. My friend Ronnie put 325 hours on his boat the first year in '87. He was the only one to ever have problem. He broke a crank playing in rolling 4 and 6's one stormy day in the Chesapeake after 795 hours. Most wore the boat out before braking any thing in the motor.

Those 330's were great motors. Interestingly the 30 Velositys would out run all other 28 Bajas,and 30 Scarabs with Magnums and 420's.

The good old days.

I agree, Lugging it down in the low 4's by overpropping it is probably worse for it. 4600 to 4800 Is best and faster too.

Jim,

Now I'm curious. I've got a pair of '94 454/330's in my Dominator. Roughly 500 hours on them running through 25 pitch Mirage props. Is it really safe to run them up that high? Thought the cast internals wouldn't hold up to spinning that fast??

425 hrs is nothing for a 330. Spin it up to 4600-4800. It won't make hardly anymore power past that point.

I agree, add another 1000 hours then you can worry.