Need help with setback

[bsullivan403]

I have an 18 outlaw that was built for an i/o and im puting an O/B on it. I need to know how far back i should set the motor. I can either use an 18" bracket with a 4" or 6" hydraulic jackplate or use a set of setback brackets with the jackplate to give me less setback. Any tips or advice is greatly appreciated.

[bsullivan403]

This is a vee bottom boat that does not have a pad. Is there a formula to figure out high high the motor should be in relation to the setback? I was told that for every 1' the motor is setback the motor should be 1" above the lowest point.

[ddipert]

1" back to 1" up would be crazy high.
I'm running 16" of set back and with the above math I might have the bottom of the lower blade of my prop in the water.

I was told a good rule on my pad boat was 1" back 1/8" up. Then you will have to play with that setting a little but that gets you close and somewhere to start from.

Keep going up and when you loose water pressure or it's slower move it back down. You will not know how high to bring the engine until you pass the correct height and bring it back down.

[bsullivan403]

I was told 1 inch up for every 1 foot up. But thanks. do you think 22" of setback is too far? that would be an 18" bracket with a jackplate mounted to that. Thanks for the input.

[ar300johnson]

how much does your motor weigh? is your boat an open bow? where is your fuel tank? batteries? what prop? set back is trial and error unless you have exactly the same set up as some one who knows exactly how to set one up. good luck and take your time.

[bsullivan403]

Its a closed bow. its pretty much a small cigarette type boat. i have a 35 gal tank in the floor in the rear 1/3 of the boat. batteries are going in the back too. I dont have a motor yet but will either be a 225 or 250 2 stroke. Thanks for the advice. I didnt want to buy parts that arent going to work but i guess thats how home R and D is done.