prop for 75 starflite

[cougar1985]

ok so this year im going to put a period correct 1963 electricshift 75 hp evinrude starflite on my cedarstrip boat.the boat weights in at about 500lbs without any gear or motor.its the boat in my avatar.i have 2 10x10 props now .i dont really think they will be right for this light a boat ,i would think 10x12 most likely.still too early for boating up here but getting closer fast.i will have to hook up a tac if at the very least temporaily so i run in the right range at wot.i currently have a 1982 90 rude on the back which pushes her to the mid to high 40,s.i find that even with a trolling plate down she glides through the water too fast for trolling.any ways the 75 will look way better on the back as its more in line with the style of the boat.any thoughts on the prop selection(not many choices for this year)?though i dont really care too much about losing speed how do you think the 75 will preform?the boat is 17 ft long and a beam of 70 inches.here,s a better pic of boat.

 

[steelespike]

Re: prop for 75 starflite

I'm inclined to agree.It came with a 10 1/4" x 10. 10 X10,10 X 11, 10 x 12 optional.
I would try your 10 X 10 and see what you get. You could use a tiny tach
about $40 easy to install one for your motor will work on any 4cyl. 2 stroke.
You may be able to get your 10 X 10 repitched.
I don't think the boat is intended to go fast so some of the 90s power may be wasted the 75 may surprise as the boat will run closer to its intended speed range.
I would guess mid to high 30s. It will use about 5 gal. in 3/4 of an hour at wot.
about 2.5 gph at cruise speed.Mount the motor as high as possible and still avoid venting(cavitation)may take some trial and error.Be sure it pumps water.
There is another starflite 75 post here an individual has a new 10 X 12 prop.You could pm him.

 

[cougar1985]

Re: prop for 75 starflite

I'm inclined to agree.It came with a 10 1/4" x 10. 10 X10,10 X 11, 10 x 12 optional.
I would try your 10 X 10 and see what you get. You could use a tiny tach
about $40 easy to install one for your motor will work on any 4cyl. 2 stroke.
You may be able to get your 10 X 10 repitched.
I don't think the boat is intended to go fast so some of the 90s power may be wasted the 75 may surprise as the boat will run closer to its intended speed range.
I would guess mid to high 30s. It will use about 5 gal. in 3/4 of an hour at wot.
about 2.5 gph at cruise speed.Mount the motor as high as possible and still avoid venting(cavitation)may take some trial and error.Be sure it pumps water.
There is another starflite 75 post here an individual has a new 10 X 12 prop.You could pm him.

thanks for the help.the 90,s power is definately not wasted as she hits 47.9 by gps using a 21 p prop.but as i said im not looking for blinding speed im going for looks and reasonable speed.i can get a 10x11 to try and maybe if thats not enough i might be able to get my buddy to repitch it .you know something steelespike,i never even looked at the shifter yet, i wonder if it has a plug in for a tac?i have a wood dash of course and im hesisitant to mount a tac there as i really dont wont to put a 4 inch hole there,so as with the 90 i just planned on using the tac to make sure im not overreving and then putting it back on the shelf.any other suggestions feel free to suggest away!again thanks.if i lost 10 or so mph i would be too terribley unhappy.even with the 90 i never run wide open for too long as i find if i cut back a little my fuel economy is very good ,you would be suprised ,i was.if i get 2.5 gph at cruise speed with the 75 id be happier than a pig in doo doo.

 

[steelespike]

Re: prop for 75 starflite

48 mph is certainly very respectable but I think you will agree a 500 lb boat with a fast hull would probably be around 55.
I believe the tiny tach could be used as a hand held. It uses induction by wrapping a special wire around a plug wire.It does require you order the wire in a length you need as you can't splice or cut it.
If you use a regular tach perhaps you could create a mount to attach from the back of the wood dash.

 

[cougar1985]

Re: prop for 75 starflite

48 mph is certainly very respectable but I think you will agree a 500 lb boat with a fast hull would probably be around 55.
I believe the tiny tach could be used as a hand held. It uses induction by wrapping a special wire around a plug wire.It does require you order the wire in a length you need as you can't splice or cut it.
If you use a regular tach perhaps you could create a mount to attach from the back of the wood dash.

agree on the fast hull thing this is 40 or so year old boat after all.will figure something out about the tac as the electshift has several lights and such that i will have to mount in the dash anyways plus a tilt switch also.yes i got lucky and i have the factory optional tilt which contrary to popular belief is not a true tilt and trim as it is designed to use the tilt at a slow speed and when you accelerate it automatically goes back to your original pin setting,per the omc brochure.thought at first i had a leak in the system when i was bench testing the motor till i read that brochure.still it will come in handy when launching as i wont have to lift or put down by hand.