I got a solution for the next go fast V-20

[bradford]

Originally Posted by UBHSTRY

I think I got my next hot rod boat.....a 1986 sylvan 17 ft I/o. Already on the hunt for a v8 set up so I can drop a 355 in it and use it for some fun.

My Dad and I use to own an '87 model Sylvan V-171 with the 3.0 mercruiser and alpha one outdrive.

[Curapa]

Last I saw they were retailing for around $70k a piece. To rich for my blood.

[UBHSTRY]

Originally Posted by bradford

My Dad and I use to own an '87 model Sylvan V-171 with the 3.0 mercruiser and alpha one outdrive.

Exactly the model we just got. Its an 86. I was joking about hotrodding, but not now. The 4 popper is locked up. Getting an adapter plate so I dont have to change the bell housesing, flip some headers upside down, and running out the transom. I am down to a 400sbc right now so, looks like thats what will go in the ole girl now

[RidgeRunner]

My only concern using the SB400 is the effect of salt water in and around the siamesed area of the block.. Then what heads/piston combo? Are you gonna try and stuff a long rod in or go back stock? Don't forget the steam holes, there won't be any in a new set of heads.

[UBHSTRY]

Ridge, staying freshwater :) Going to use a set of performer 90909 rpm heads. Keeping the block stock for this, I think iirc, they are 5.65 rods in a stock 400.

[RidgeRunner]

Yes sir I think you recall correctly. Getting a 6" rod in there can be tricky when ordering pistons. Stock the 400 had a small dish piston and open chamber heads. Mostly truck engines. Some like the stroker, I liked the cubes. I turned the 400 just as hard.

[bradford]

Originally Posted by UBHSTRY

Exactly the model we just got. Its an 86. I was joking about hotrodding, but not now. The 4 popper is locked up. Getting an adapter plate so I dont have to change the bell housesing, flip some headers upside down, and running out the transom. I am down to a 400sbc right now so, looks like thats what will go in the ole girl now

Would love to see some pics when you get her going. Trip down memory lane. I have a lot of good memories on that boat.

[spareparts]

If you are going to spend any money on a hot engine. You may want to consider a closed cooling system, even in a fresh water enviorment. You'd be suprised the amount of electrolysis you will find in an aluminum intake on a freash water boat, let alone the heads. Biggest advantage is you have a more even temperature across the engine, rather than hot and cool spots that you would see in a raw water cooled engine