how much in pitch should i drop?

[spacerust]

originally i had a 10" prop. ran great. didn't have a tach but rpm's sounded right and performance was good. then had a spun hub. after discussions with a tech he said wrong size prop, should have around 15-17. i got a 15". ran but at wot only was going about 8mph according to my gps. really disappointed. should i go back to the 10"?

 

[Dhadley]

Re: how much in pitch should i drop?

We're guessing at rpm and so is your "tech". We're also guessing at what boat / motor we're talking about.

Without the acurrate rpm it's almost impossible to make a judgement call.

 

[steelespike]

Re: how much in pitch should i drop?

Very difficult to tell where your at without max rpm and speed and
description of boat and motor.Old prop could be rehubbed.
Wrong prop/rpm can result in premature engine failure. both too high a pitch and too low.A Tiny Tach is easy to hook up can be used on similar motors without regard to polls etc.priced around $40.