Prop for Erude 88 spl

[dieselcat]

I have a landau pro 17,aluminum bass boat with a 1987 88 spl on it.The power head is an 87 but the rest of the motor is a 1995.
I currently have a SS 13.125 X 19p Michigan wheel prop on it and get 4900-5200 rpm at WOT depending on how i have the motor trimmed.
I get a decent hole shot with this prop and i do mostly river boating,going down river i get right about 43-45 MPH and up river 35-37 MPH.
My ? is if i went to a 13.125 X 17p would my speed and fuel millage be better or worse.

 

[DJ]

Re: Prop for Erude 88 spl

Almost every "crossflow" V-4 I've set up worked best with a 13 1/4" X 17" prop.

At a WOT of 5200, you are lugging the engine. It doesn't like that. The 17" will get you very close to where you need to be-5500.

 

[steelespike]

Re: Prop for Erude 88 spl

Its very difficult to estimate prop results without collecting very spicific info.
There is a form at the top of the page.No doubt the motor would be happier at
the higher rpm.Your motor will use about 8 to 9 GPH(gallons per hour)at wot(wide open throttle)regardless of which prop you run. The idea is to get the motor within its best rpm range and attain the best speed at a given rpm.
Based on the speeds you have listed I would say your close to your max.
Before changing props you might consider raising the motor a hole or 2 to a point just before venting(cavitation) becomes a problem.Could result in a couple of mph under ideal conditions.Also could add some rpm.The right prop could result in the highest setting and rpm/speed improvement.

 

[dieselcat]

Re: Prop for Erude 88 spl

Its very difficult to estimate prop results without collecting very spicific info.
There is a form at the top of the page.No doubt the motor would be happier at
the higher rpm.Your motor will use about 8 to 9 GPH(gallons per hour)at wot(wide open throttle)regardless of which prop you run. The idea is to get the motor within its best rpm range and attain the best speed at a given rpm.
Based on the speeds you have listed I would say your close to your max.
Before changing props you might consider raising the motor a hole or 2 to a point just before venting(cavitation) becomes a problem.Could result in a couple of mph under ideal conditions.Also could add some rpm.The right prop could result in the highest setting and rpm/speed improvement.

Already played with motor height,i got it on the second hole now.if i go up any higher in makes the boat bow hop to much and i get alot of prop spin.

The year of the boat is 1996,landau pro 17.it is acually 16' 10" i have no idea of what the weight might be,anywhere to find this out?

 

[steelespike]

Re: Prop for Erude 88 spl

Are you talking about vertical height or 2nd hole trim setting?
You might find the weight at the NADA appraisal guide.
I checked; it appears it weighs 500 lbs dry really light, seems to me the 19 would be pretty close for that. Maybe a prop shop could remove a little cup.
Might reduce the bow hop and I've seen it really help both speed and rpm.
Seems it would cost less than a prop.

 

[dieselcat]

Re: Prop for Erude 88 spl

Are you talking about vertical height or 2nd hole trim setting?
You might find the weight at the NADA appraisal guide.
I checked; it appears it weighs 500 lbs dry really light, seems to me the 19 would be pretty close for that. Maybe a prop shop could remove a little cup.
Might reduce the bow hop and I've seen it really help both speed and rpm.
Seems it would cost less than a prop.[/QUOT


I'm talking bout the second hole on the mounting plate on the transom,i got it on the second hole down.The motor sits up off the top of the transom an inch or just a tad more.

I mounted it just as the other motor was when i did the swap.The anti ventilation plate is an inch to an inch and a half above the bottom of the boat.The boat has a slight V all the way back.

If i went to get a little cup taken outa the prop how much should i tell em to take out?

Will post pics of the prop so you can give more accurate advice.

 

[reelnative]

Re: Prop for Erude 88 spl

I would stick with the 19 your boat is light and your not lugging it as another poster said your in the proper operating range at 5200 wot is 5000 to 5500 on that motor