prop question

[fountain]

I have a 90 hp suzuki with a 14 x 20 ss prop on it turning about 6500 rpm at wide open throttle, max rpm for this motor is 5500 i think. what prop do you recommend

 

[steelespike]

Re: prop question

Need boat size, type and weight.rpm and speed by gps is best.
assuming a light fast boat and tach is correct you need a 25" pitch same make/model prop.Would put you at 5,500.
Without the info I suggested there is no way to know if the rpm makes sense.

 

[Turbo1]

Re: prop question

2-stroke or 4?????? You may not be that far off...

 

[fountain]

Re: prop question

boat weight with fuel is about 2000 lbs type is a 18' v hull and im not sure about the speed if i had to guess around 35 mph

 

[fountain]

Re: prop question

its a 2001 4 stroke

 

[steelespike]

Re: prop question

I think I would check the tach before making any changes.That seems like a lot of rpm from that setup.You better check the recommended max rpm I think the 4 stroke may be around 6,000.

 

[fountain]

Re: prop question

How could I check the tach, and my book says max rpm is 5500

 

[steelespike]

Re: prop question

boat weight with fuel is about 2000 lbs type is a 18' v hull and im not sure about the speed if i had to guess around 35 mph

I don't think you can push a 2,000 lb boat at 6,500 rpm with a 20" prop.
My bet is the tach is set wrong or is defective.