transom notch width

[WillyC]

Hey guys,
I think this has been discussed before but I can’t seem to find it. I want to know what the minimum transom notch width would be for a 20' sf. I'm about to cut the new core material and I'm thinking that it could probably be a little narrower than the original set up. I will be putting either a yamaha 150 or 200 (carburetor version) when I get things finished. The motor will be new and will be installed with the sea star hydraulic set up. The width of the original transom notch is 43 inches at the top and 33 inches at the bottom. Thanks -will

[riffraff]

Wow, I was just looking for the exact same info. My fiberglass guy is working on the transom now and I am bringing it up 5 inches, but not sure of the notch width..

[WillyC]

O yeh,
I forgot to mention that I will be raising the transom by 5 inches too.

[alejmend]

Hey Will & CSC Members,

Did you ever figure out the width of the transom notch? My notch is 44" at the top and 33" at the bottom( at the 20" transom height area). I am raising it to 25" but would also like to narrow the notch. Any idea as to what the minimum clearance width you need for a single engine set up? (20'cc)?

-Alex

[muddywater]

I remember that Will had measured my transom notch when I bought mine because my boat's transom notch (1972) was skinnier than his (which I think is a 78 right?). I think he decided his was set up for twin 70's or something.

Anyway, my original 20" height transom is about 33" wide at the top and about 22" at the bottom. Keep in mind those measurements could be an inch off since I have a motor in the way. If you raise it 5" the bottom width would of course be a little wider since the sides are at an angle. Although the motor has plenty of room, I am not sure about the Seastar system since I don't have one (yet)

[oldbluesplayer]

a while back several of us 20' Seafari owners were comparing this same thing, and we identified three different transom configurations, a narrow, a medium, and a wide notch version.

Mine is the narrow version, and on a 20" transom, is also 22" across the bottom, and 33" across the top. The medium version is a little wider, and appears to be spaced / sized for a pair of, perhaps, Johnson 70hp triple cylinder in-line engines, or even the old merc in-line 6's. Then we have seen a Seafari with a full transom width notch, and splash board configuration, that a couple of V-4 engines could easily be hung on, though that would be way too much weight.

A V-4 Johnson easily fits in the 22" base level notch, with full side to side swing clearance.

hope that helps.

Bill