hey guys, i have a 25 kohler longtail on a 14/42 and it runs 18mph @ 3980 rpms. trying to get more any ideas? maybe bigger carb, more timing, headwork? any advice would help.

What is your prop condition? Rpm sounds high for that speed. A good 9x6 will run 20 at 3800. Does your prop have a good cup around the edge.

by myself with my 25 kohler long tail i get about 22 or 23 with just 6 gallons of gas and one battery two people and a ice chest of beer i get 20

I run a 25 hp LT on a 16x36 jon boat.

With just a tank of gas, me, and my 12 year old daughter, we get right around 20 mph (GPS).

I have a beat up 9x5 prop. I imagine if I get a 9x6, knock some dents out of the bottom, sand it and put a coat of Gator Glide on it, I may bump it up to 23 mph.

with four people in it, it still chugs along, and gets us back to where we want to fish, and sure faster than my old 14 foot with a 36 lbs thrust trolling motor.

I got a 9x7 I believe I would have to check when I get home but with the heaviest load ive had in it which was me 145# my prego wife 150# 6 year old daughter 35# and buddy 285# six gallons of gas and battery I can run around 15 or 16 mph

How do you tell what prop you have?

measure from one tip to the other

226scot, sometimes the size / pitch is stamped on the prop hub or prop face. If it's not marked or wore off I think a prop shop could tell you how to measure pitch too.


guidry21, would a 9 x 8 give you even more deepwater speed?

Great speeds, guidry21! If I could manage that with my 27 Lt on my 1648 grizzly I would be jubilant. I get 20 mph just me and 17.5 mph two hunters and gear. My hull just plows too much. I do use a 9x6, 'cause the 9x7 runs several hundred rpms slower and the top end is 2 mph less. 228scot, I agree with Olschool that your prop is probably well worn...time for a new one.

i just measured my prop and it is 8" and from what yal say it should be 9", am i correct?

You could be running an 8x4 i think the size is yoy could always look up the mfg and see what size prop they recommend i got more speed by adjusting the tip on my cav plate cause mine use to run real deep and i would only get like 18 wot as far as 9x8 getting more speed in deep water i would assume it would but not real sure i know with a bigger wheel youll turn up less rpm

went to go devil it came with 9x6, ganna buy new prop any thought on whos prop to buy?

Your prop is shot. Get a 9 x 6 from Godevil.

Depending on how much "cup" you get put on the prop a 9 x 6 prop will measure 8 3/4 or so.

ok thanks for the help