what size should I go to 90hp

[johnson89]

1989 90 hp johnson. boat with all gear is around 1400lbs. 15.4 bass boat....it has a 14x19 prop and the motor is doing 6000 plus, not sure how much more has I back it off as soon as I saw it was pass 6000 rpm's....I just finished doing a tune up on the motor ( bought used ) and the timing was off and the motor would not open too WOT, got everything set good now but the rmps' are way up there...thanks for any help

 

[Bifflefan]

Re: what size should I go to 90hp

That depends,
There is no law that says you must have the throttle slammed open. You can adjust it so you stay in the max rpm range.
You can jump to a 21p and keep the RPM's down some, but may loose more than you bargin for in the mid and lower ends.

I guess what im asking is, does this prop suit your all around needs or do you need to be going "hell bent with your hair on fire"?

 

[johnson89]

Re: what size should I go to 90hp

well the hole shot right now is very fast, even at 4000 rpm if you touch the throttle it will set you back in your seat.I might just run it like this for a while an see how it goes.I don't ski so the hole shot is not too important.Some of the areas I like to fish has some good size lakes and a lot of diffrent lakes that connect too give you 28 miles of waterway...I was looking at the 21pitch but almost all of them are in the 13" dia. I assume I would need a 14X21 too bring down the rpm's....

 

[sublauxation]

Re: what size should I go to 90hp

diameter shouldn't make much difference.

 

[johnson89]

Re: what size should I go to 90hp

well I finished the boat, got 2 more batteries, toped off the gas tank 18gal., filled both livewells full of water and my rpm's are now 5800-5900, so i will just adjust the throttle and get it around 5600 an leave it there. gives me some room if i add some weigh, an stills get me on plane in about 3 sec.s.......

 

[Bifflefan]

Re: what size should I go to 90hp

well I finished the boat, got 2 more batteries, toped off the gas tank 18gal., filled both livewells full of water and my rpm's are now 5800-5900, so i will just adjust the throttle and get it around 5600 an leave it there. gives me some room if i add some weigh, an stills get me on plane in about 3 sec.s.......

I think thats a good plan, at least until you see how she goes with a couple buddies with their gear and a case of adult beverages out for a day fishing.