# 150 yamaha 4 stroke



## reeltrouble (Oct 3, 2007)

anyone know how to make this thing go any faster! its on a bay boat it does 46 and i want to go faster it has a 3 blade 14 1/2 x 17 stainlessprop and turns 6200 i run it at 6000 and no jack plate or a little less it runs 47 1/2 at 6000 with an aluminum prop and no jack plate. 

if i had a jack plate and 14 x 20 prop do you think i could make 52 mph @6000 rpm?


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## fishingfromagunship (Oct 26, 2007)

I'd have to know what kind of torque that 20 prop was putting out. Ideas like this are what lead to engine failures. The motor can only produce so much horsepower, which is a product of your torque and your RPM. Exceed it, and you're likely to pop a piston, valve, or worse. Some of the smart guys on here should be able to help you, though. I know for a fact that you'll definitely cause more wear on your motor than designed for if your original setup was stock.


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## DOUBLE "D" & LV (Oct 2, 2007)

I would go with a stainless prop to begin with. It will give better performance usually. I would go to Accuprop next to Bahia Mar and see Danny. Tell him what you have and he will give the best prop setup for your application. He may even have a few to test with. Another performance item would be engine height. I would recommend having someone look at that to see if it is set correctly. If it can go any higher, some of the drawbacks are blowouts in turns and prop venting when trimmed in waves. This is why I say to have someone look at it for the height.


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## X-Shark (Oct 3, 2007)

> f i had a jack plate and 14 x 20 prop do you think i could make 52 mph @6000 rpm?




First is the boat have a Tunnel Drive for this? If not it will just blow out. I do have a Bob's Jack Plate on my 162 Scout. I mainly use it so I don't have to tilt the motor to trailer the boat. I also use it in shallow water to keep the motor out of the sand.



Sound's like your a speed Demon. Just bolt a bigger motor on it.



Typical Tunnel Drive.


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## DOUBLE "D" & LV (Oct 2, 2007)

ooh, let's put twins on. :letsdrink


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## sailsunfurled (Oct 2, 2007)

Heck I dont mind running in the 40s. When you put the twins on it, I take the 150 that you have now.


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## wrightackle (Oct 29, 2007)

I would be interested to know what lengthbay boat you have.I had a key west 19'6" with a 150 two stroke and it would only do 47 mph. You might check out yamaha's web site and look at some of their performance bulletins for that motor. You might get lucky and find your boat with that particular motor on it. That could give you some helpful guidelines.


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## Death From Above (Sep 28, 2007)

I have the F150 with that same propon my Nautic Star 1900 Bay. It will do 53mph at 6K rmp with just me and a tank of gas. Drops to 48 with 4 adults. Don't see a need to go any faster.


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