1987/1995 88 spl erude

[dieselcat]

i have a erude 88 spl,the powerhead is an 1987 but rest of motor is a 1995.i have it on a 1996 landau pro 17 aluminum bass boat.i am currently running a michigan wheel apollo 13.25X17p,stainless steel and getting 5000-5200 RPM at WOT and 36-37MPH up river and 42-44 MPH while going down river using GPS.i dont really know what it will do on a lake [calm water]as far as spped but when i go in the slues off the river it does 39-40MPH.

my question is,is there another prop that i could get to give me more speed without sacrificing RPM and holeshot,what all plays part in this stuff other than dia and pitch?i know the basics of props and how they work but dont know anything about the rake and other stuff if there is any?

thanks in advance,shane

 

[steelespike]

Re: 1987/1995 88 spl erude

Top speed and hole shot don't go together.Prop selection is a compromise if you want both.If you want the best of one you sacrifice the other.
Using 39 mph and 5100 rpm 2.00 ratio 17" prop your slip is about 4%, you can't do much better than that.
Typical slip is about 8 to 12%.You could try raising the motor.If you don't have any venting(cavitation) problems the motor may be too low.Raise the motor to a point just before venting becomes a problem.
Be sure the bottom is clean and smooth,motor in excellent tune with good compression.
Throttle opening all the way.

 

[dieselcat]

Re: 1987/1995 88 spl erude

Top speed and hole shot don't go together.Prop selection is a compromise if you want both.If you want the best of one you sacrifice the other.
Using 39 mph and 5100 rpm 2.00 ratio 17" prop your slip is about 4%, you can't do much better than that.
Typical slip is about 8 to 12%.You could try raising the motor.If you don't have any venting(cavitation) problems the motor may be too low.Raise the motor to a point just before venting becomes a problem.
Be sure the bottom is clean and smooth,motor in excellent tune with good compression.
Throttle opening all the way.

when i installed the motor i played with raising and lowering the motor on the transom,if i go up 1 more hole then i get prop spin real easy unless motor is trimmed all the way down,so im guessing i got it bout as good as its gonna get IMO.
what exactly does a prop with more or less rake do or not do?ive looked all over the web and im not finding what im looking for unless for some reason im missing something.

 

[82rude]

Re: 1987/1995 88 spl erude

as i understand it more rake helps with bowlift.check this site out .About Boat and Marine Propellers (props)

 

[V153]

Re: 1987/1995 88 spl erude

At 5100 rpm you're just beginning to get into that motor's powerband. They can run 5500 all day. My old 90 was routinely wound up in excess of 6K for short periods.

As SS said that's about as good as it's gonna get with your current set-up slip wise. I would look for a prop that produces alotta bow lift. I have a Quicksilver Lightspeed that generates an amazing amount. Raker is another one.

Playing the prop game can prove to be an expensive frustrating proposition, cuz nothing is set in stone. And every boat behaves differently. Your best bet is to make friends with the local prop shop. Then see if they'll let you test a couple?

 

[dieselcat]

Re: 1987/1995 88 spl erude

thank you all for the info!