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engine swap into non-subaru... which one?

09-01-2006, 04:59 PM
Make a long story short.... I'm trying to see how feasible it would be to use a subaru engine in an inboard/outboard marine application. There are several hurdles to overcome including marinization parts, connecting it to the outdrive, etc which are pretty easy for an engineer/fabricator like me, but I need Subaru-specific help from you.

So here's the recipe I would basically need:

-weight is not much of an issue since it would be replacing an iron chevy V8, but the lighter the better
-detuned for lower RPM use; shooting for 200-225 hp, all available by no more than about 5000 rpm
-turbo is great since I have access to cool lake water for an intercooler
-must be 87 octane since that's all that is available at the places I boat. That should be pretty easy with cool lake water all around.
-possibly a link to some suby performance FAQs?


09-03-2006, 06:12 PM
The turboed Subaru engines won't run on 87 so you may want to look for a earlier 2.2 or 2.5 engine and work with that.
Keep in mind that some years like the '98 didn't like lower octanes, whereas others ('02 - '05 RS engines) will run on 87.

You can get 200hp plus out the RS engine if you're willing to go that route, but based on the fact you won't have high octane available I suggest you forget any of the turbo generations.

09-05-2006, 01:38 PM
Ok, good stuff. What about maybe an EG33 like from an SVX. Good engine? Bad engine? IIRC they were 270hp from the factory, so I should be able to get 200 or so from it in a marine application.

09-05-2006, 01:42 PM
I'm sure youre aware of this, but there are plenty of supercharged EJ25's that are used as kit plane engines. I know of 5 or 6 ppl that have fabbed a mercedes supercharger onto their 2.5s and put out around 230 - 250.

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