Gas?

bluball

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I just put a new Yamaha sho 225 on my boat. The book says to run 89 octane non ethanol gas in it. The problem is most stations near me only have 87 non ethanol. Is it better to run 89 ethanol or 87 non ethanol if I have to choose? I am going to flash the Ecu to 300 HP soon if that makes a difference.
To a 300,guys coming in the shop are getting There's flashed to a 326😀
 

bluball

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As others have stated, non ethanol only. Where do you go to find out if a motor ECU can be flashed? Wondering if my 2021 SHO 150 can be…not sure how it would make a difference it already runs at 6000 ROM WOT. I'd have to change the prop I guess??
Matt Moore Jackson tn.,think you can flash a 15 to a 200
 

bluball

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What gains do you expect to see with 75 more HP?
Lots,a customer has a 520vx ranger and is running 75mph with a 200 yamaha sho.Its not when broke in yet,will probably run alittle faster.They say the torque out of the hole is amazing.
 

BuckWild

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Had a guy here at the river that had a 27 foot Rinker cuddy cabin with a merc 454 inboard. Top speed 47 mph.

Like an idiot, he dropped 10k on a custom built, 700hp naturally aspirated big block.

Top speed after doubling HP...52mph.

I have a 27 foot Tritoon with a Merc 350 Verado. Top speed 62mph with two people and 66 gallons of gas. How much faster do you think a Tritoon with twin 350 Verados will run?
 

bluball

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Had a guy here at the river that had a 27 foot Rinker cuddy cabin with a merc 454 inboard. Top speed 47 mph.

Like an idiot, he dropped 10k on a custom built, 700hp naturally aspirated big block.

Top speed after doubling HP...52mph.

I have a 27 foot Tritoon with a Merc 350 Verado. Top speed 62mph with two people and 66 gallons of gas. How much faster do you think a Tritoon with twin 350 Verados will run?
We are talking about a 20 ft ranger hull that doesn't have a fast hull doing 70's with a 200hp engine.My 19ft triton is more of a speed hull and I get 56mh with a 150hp motor.Another local guy with a Allison had a mercury 250r and switched to a flashed yamaha 200 and it's faster than the mercury motor.A mercury 250r,the r stands for racing.
 

BuckWild

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We are talking about a 20 ft ranger hull that doesn't have a fast hull doing 70's with a 200hp engine.My 19ft triton is more of a speed hull and I get 56mh with a 150hp motor.Another local guy with a Allison had a mercury 250r and switched to a flashed yamaha 200 and it's faster than the mercury motor.A mercury 250r,the r stands for racing.
And my 17.5 foot aluminum boat with a 150 merc tops out at 45 mph. Your boat is longer and heavier than mine but runs faster. That is a result of hull design or prop size.
 

double browtine

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I would go with the non-ethanol 87. However if you are going to have it tuned to make more power, it's going to need more fuel. They are going to increase the timing (advance it), so going with the 93 octane will help with detonation.
 

TRIGGER

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Sep 25, 2011
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Cunningham TN
As others have stated, non ethanol only. Where do you go to find out if a motor ECU can be flashed? Wondering if my 2021 SHO 150 can be…not sure how it would make a difference it already runs at 6000 ROM WOT. I'd have to change the prop I guess??
Your 2021 sho can be flashed. Just asked the guy that's doing mine (Dave at Anderson marine). They have or are getting the software soon to do them in house.
 

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