help transom design, vote!

[chevyrulz]

kinda bored @ work, figure i will see if i can get some input from all of you experts on my next build project. so i'm mounting a longshaft 30hp evinrude on a 1436 alumacraft designed for a short shaft motor. 22" from motor mount to cavitation plate, & 16" transom, the motor needs to come up at least 5 inches based on my best guestimation

i'm going to use a sleeve style jack plate made of aluminum to reinforce & raise the height of my transom. i'm undecided about having the sleeve go full width or just wide enough to mount the motor? it's a tough decision, because the strength i gain by going full length will be offset by the additional weight. the sleeve is super thick, like 1/4" or more & heavy as hell, plus i'm already overpowering the hull by putting a 30 on there, so anything i can do to minimize stern weight will be a good thing. BUT if i go full length, it will reduce the amount of water that comes over the transom. if i go full length, i'll have to fit the sleeve around the knee brace on the transom, by cutting a slit in the sleeve.

let me know what y'all think by posting or voting. i'm wondering if i should go full width or minimum width, & whether i should angle or round the corners. also, i can wait for ban saw to do this, or i can attack it with the angle grinder :shock: here's a few pictures:

 

[lovedr79]

the pic you have here is basically how mine is setup. works great!

 

[krawler]

I vote "none of the above" Sell the motor and get a nice 15 or 20hp short shaft.

 

[bigwave]

I say full width.....if you need to add some float pods and get an even bigger engine......j/k about the engine, but if your going to mod the transom you might as well make is bullet proof and add the pods if necessary.

 

[BigTerp]

I vote minimum width, just because that's what I'm planning on doing to mine to mount a 50/35 Johnson jet that I need to raise up about 5 or so inches. Can you give some details about the transom riser/jackplate you made? I need to figure out how I'm going to go about making one for myself.

 

[chevyrulz]

I vote "none of the above" Sell the motor and get a nice 15 or 20hp short shaft.

aw that's no fun, thank you though, poll edited for ya

the pic you have here is basically how mine is setup. works great!

good to know, thanks!

I vote minimum width, just because that's what I'm planning on doing to mine to mount a 50/35 Johnson jet that I need to raise up about 5 or so inches. Can you give some details about the transom riser/jackplate you made? I need to figure out how I'm going to go about making one for myself.

strictly speakin on looks, i like the minimum width too. the transom sleeve i have, i did not make. someone else made it to put a huge motor on a fastcraft, which is a very small fiberglass boat. i just lucked out they never used it & it fits my transom thickness perfectly.

let me know if what i'm about to say doesn't make sense regarding mor info on the sleeve: it appears to be 1/4" thick aluminum plate. they put the plate in a metal brake, likely using heat (not sure didn't make it), and then bent a 90 in it leaving about 2". then they welded a rectanglular aluminum tube inside that 90 degree bend leaving 1/4" ear where they welded a matching size aluminum plate to the other size to complete the U shaped sleeve.

I say full width.....if you need to add some float pods and get an even bigger engine......j/k about the engine, but if your going to mod the transom you might as well make is bullet proof and add the pods if necessary.

my buddy, who gave me the sleeve/jack said to go as wide as i can too, i'm thinking that's my best bet. hopefully i won't need float pods, good idea

 

[chevyrulz]

click my build link in my singature to see the transom sleeve installed