Advice on Prop replacement

[fisheye]

I destroyed my prop at Nolin over the weekend. I have a 90 Mercury. the prop that was on it was a 12.5" X 23 pitch. I can get a good price on a new prop that is a 12.75" X 21 pitch. My question is will this prop provide the same performance as the orginal prop?

[Guest Author]

You can plan 200-400 per pitch. The 21 pitch will add 400-800RPMs to your WOT. If your other prop performed satisfactory, than stay with that diameter and pitch, however if you need more RPM than you may be ok with the 21p...Good luck.

[CTFSHWHISKER]

Hard to say without trying,diameter can change performance just like the pitch,find someone who has that prop and try it out,otherwise i'd find what you had if it performed well.

[DSW]

Sorry about the last note, I didn't catch that the diameter was larger. I thought the only difference was the pitch. I'm not sure what it will do by going up in diameter and pitch. I would still guess more power in the hole shot, but I'm not sure about speed. It might be that if your engine can push the larger diameter, that might compensate for the pitch change.

[DSW]

It should give you more on the low end and less on the high end. In other words, a faster hole shot but less speed. It may allow your engine to overtac as well.