Hydro design for big guy.

[Alaskanrocket]

Hey,
Im obviously a newbie with a newbie question. First off I'd like to say I know nothing of Hydro racing. I collect old outboards and old outboards is all I know and that is the extent of it.
I have a couple of Merc Mark 25's One is restored the other has a good powerhead but l/u is shot. I want to put the good powerhead on a KG lower and build a motor to put on a hydro.
I have been recently looking for plans for a suitable hydro. Cheap and simple would be best. I would prefer a 3 point or a similar classic design. I have been looking for plans all over the place for about 6 months. I just don't know what is going to work for me as I know not much about hydros. Im a big guy 6'3" 275 lbs. Most of the plans I see are suited for smaller people. This is strictly for fun on some of the local lakes. Im open to whatever suggestions you guys have for me. Thanks alot in advance, and I attached a picture of one motor in my collection you guys might like. Jess
P.S. I haven't touched this motor, this is how I got it.

[Fast Jack]

lake boat

If you want a lake boat for the 25 rat motor -look at a Hal Kelly "wetback " Plans and a kit are available from Clark Craft , easy to build and with a center fin is easy to turn. If you want to run the D mod you could build the same boat larger .

[sam]

I agree, the large version of the Wetback or large version of the Ben Hur should carry you well.

[ZUL8TR]

Hydro

If you want a lake boat for the 25 rat motor -look at a Hal Kelly "wetback " Plans and a kit are available from Clark Craft , easy to build and with a center fin is easy to turn. If you want to run the D mod you could build the same boat larger .

Good choice of hydro but the Clark Craft kit comes with marine fir plywood that includes football plugs where nots were. Fir ply is a PITA because of the grain checking that occurs in high stressed transverse bending areas like between stringers (especially 1/4" thick) and the sun for topside applications. Solution is to fiberglass with epoxy resin. The Wetback needs Ocume which is more stable and no grain check.

[Alaskanrocket]

I wonder how much a kit would cost to get shipped to alaska? Thats pretty much out of the question. The other problem is I don't think I can find Okume up here. Im not sure. If I can Im sure it will be over 100 a sheet. I checked into it about 8 years ago and it was 75 for a sheet of 3/8". I like the wetback and I was leaning towards that. I'll have to look into the plywoods some more. I wish I could get away with exterior. Jess

[ZUL8TR]

Hydro

I wonder how much a kit would cost to get shipped to alaska? Thats pretty much out of the question. The other problem is I don't think I can find Okume up here. Im not sure. If I can Im sure it will be over 100 a sheet. I checked into it about 8 years ago and it was 75 for a sheet of 3/8". I like the wetback and I was leaning towards that. I'll have to look into the plywoods some more. I wish I could get away with exterior. Jess

You can get along with exterior fir ply because the glue is the same as used in the marine grade. The only difference in Marine is the quality of the interior plys as to voids. There may be small voids in the exterior grade. Given that you will still have to do some fiberglassing in critical spots to prevent the grain checking that fir ply will have.

Here is another choice for a kit. His C or D stock will be a nice ride for your engine. Although not the classic design like the Wetback but he offers a kit with Ocume ply, all the framing, nails, glue, rigging, etc.

http://www.boatracingr11.com/sorensenmain.htm

[johnsonm50]

I agree with ZUL8TR, on the ply, It also makes the B Wetback 175 lbs, a bit over the plans specified weight. A guy your size would need a D sized or about 15% larger. The MK25 is a good runner but maybe not enough, the 4cyl.. that'll do nicely if you can run it. You can find plans here http: boatsport.org Looking for a used D or E-F boat would be worth looking into. Running the next size up boat for the motor you have isnt a bad idea for fun running. Good Luck

[Alaskanrocket]

The cylinders and assuming pistons are shot on the mk55. Its going to have to be the mk25 for now until I can find a new cylinder head for the mk55. I haven't ripped it apart yet but when I brought it home the cylinders were full of water and rust.