Altitude verses rpm?

[NM Wolffman]

I recently moved from sea level to 5000 foot elevation. What a surprise when I launched my boat at Elephant Butte. Hole shot was gone. Took what seemed like half a footbal field to get on plane. Started asking why and was told I need to re-prop.

I have 89 Champion Mean-15, 89 120 Evinrude and 6" Jack Plate. Current prop is 23 re-worked SST that was perfect in FL, LA, and SC. Great hole-shot and top end speed of ~60 (RPM of ~5500).

I thought I needed to re-jet, but local mechanics so no. They tell me to re-prop. I'm only going to be here for a few years and don't need/want to spend a fortune on a new prop. Also props are not as plentiful here in NM as they were back east. I'm looking at going with a 19 pitch Michigan Wheel Rapture ($130). Will this prop give me my hole shot back? I know I won't see speeds of ~60 up here, but that's ok as this is a temporary move.

Any ideas?

[RUSTY63]

I agree with the mechanic, re prop.

The 19 should give you your hole shot back just make sure it keeps the RPM's around 5500 on top.

[NM Wolffman]

Thanks Rusty,

When you say keep it around 5500, it that the max or recommended rpm? What is the power band for my 89, 120 Evinrude? In other words, at WOT what range should my rpm's be? I don't want over-rev or under use.

Thanks again for your help.

[RUSTY63]

The operating range for your motor is 5000 to 5500.