Cruising RPM for FV 250 with 5.0MPI and B3

amajamar

What is your approximate rpm while cruising on plane with that setup?  I'm new to boating and don't really have a feel for what max should be.  My boat seems like it wants to plane nicely at about 4000, but that seems high to me.

Thanks in advance!

Black_Diamond

Without getting into the prop pitch discussion (a lively one!) your rpm is about right. Don't confuse your car rpm to a boat rpm.

Lifes Good

BD is right. Generally the RPMs for a 5.0 is about about 1000 off from speed.  Ie. 4000 = 30 mph.  Give or take.  Now a 5.7 the range will be closer.  4000 would be around 35 mph and a big block at 4000 might line right up at 40 mph.  So those of us with smaller blocks and think we are saving gas.... Well we are not.  Our engines have to work a bit harder than big blocks, hence higher fuel consumption!  Therefore the opposite as for a car.

Maverick

Sounds right! 4000 = 30 mph, 4800 wot around 36 mph (5.0 mpi with Alpha One gen 2) quite heavily loaded, OK no pitch discussion but I have a nice stainless prop! I agree with Lifes good re the fuel consumption and that extra 800 rpm and 6 mph gets very thirsty!