Prop Guru's Have A Look, Sea Ray, Alpha 1 with 350TBI. Best Speed Prop

[Alex_AGB]

This is what I have?

.2000 Sea Ray 230 Overnighter. (Clamed dry weight 4000 lbs)
.Merc 260hp 350TBI
.Alpha 1 with 1.47r ratio
.Vengeance 48 16314 17P prop (stainless)

With around 110 litres of fuel. Me and another passenger (400 pounds)
At 48-49 mph on the speedo and 48.5on the gps I was turning 4900rpm

I usually spend most of my time cruising around 3000rpm and 25-26mph but I?d like to pick up a few mph top speed if I can.

Let me know if I left out any info. Thanks

 

[180shabah]

Re: Prop Guru's Have A Look, Sea Ray, Alpha 1 with 350TBI. Best Speed Prop

I?d like to pick up a few mph top speed if I can.

Your prop is good, 9-11%slip. You need to make more power, 300 neighborhood.

 

[joker650]

Re: Prop Guru's Have A Look, Sea Ray, Alpha 1 with 350TBI. Best Speed Prop

Your prop is good, 9-11%slip. You need to make more power, 300 neighborhood.

How do ya figure that out??

 

[180shabah]

Re: Prop Guru's Have A Look, Sea Ray, Alpha 1 with 350TBI. Best Speed Prop

How do ya figure that out??

I cheated

 

[Alex_AGB]

Re: Prop Guru's Have A Look, Sea Ray, Alpha 1 with 350TBI. Best Speed Prop

Thanks 180shabah! Since I've maxed out my top speed is there a prop I can get to improve fuel mileage at cruising speed?

 

[180shabah]

Re: Prop Guru's Have A Look, Sea Ray, Alpha 1 with 350TBI. Best Speed Prop

Cruise economy pretty much follows correct prop selection. I am bot saying that you couldn't improve it, but boats are just so inefficient, it takes a really long time for that mpg increase to pay for the prop that achieved it.

Your best bet, would be to install a flowscan. I bet you would be suprised to learn your TRUE best cruising RPM/speed.

 

[Alex_AGB]

Re: Prop Guru's Have A Look, Sea Ray, Alpha 1 with 350TBI. Best Speed Prop

Cruise economy pretty much follows correct prop selection. I am bot saying that you couldn't improve it, but boats are just so inefficient, it takes a really long time for that mpg increase to pay for the prop that achieved it.

Your best bet, would be to install a flowscan. I bet you would be suprised to learn your TRUE best cruising RPM/speed.

Thanks again. Where do I get a Flowscan? right now at 2800 rpm, 25mph and light wind I burn around 18-20L or 4.75-5.28 gallons and hour