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3.0 performance upgrade

$$BOAT$$

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I know, I know. There ain't much to do with my lil 4cyl. But, has anyone swapped a 4.3l in, for the 4 cyl? I'm curious if it's worth it, or do I need a new drive to handle the extra power? Or, is the only way to do it is if my boat came with that engine as an option? I've got a spare, machined, 4.3 block.?? Any ideas?

Since mine is rebuilt, I could always port n polish the head, cam upgrade, ? Looking at other posts, it doesn't look to friendly of a topic, lol
 
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Do yourself a HUGE favor: live with it as is. If you gotta own a muscle boat, sell yours and buy one. Seriously.

Jeff
 
Ayuh,..... Either live with what ya got, or buy a faster boat,.....

Goin' to a 4.3l means up-gradin' everything from the pulleys to the prop,.....
 
Boat engines do not behave the way car engines do. Port work benefits only at the top end where air flow is at max and you're trying to flow more. Since boat engines are literally incapable of ever making redline, your efforts are wasted. In addition, adding ten more horses will probably only gain you at most another knot's worth of top end speed.
In this case there really is no replacement for displacement. A 454 doesn't have to work as hard as a 3.0 to move the same boat, therefore could have higher top speed as it won't "hit the wall" as soon.
 
Best performance upgrade I did for my 3.0 was buy a bigger boat with a 5.0.

Seriously I had one for 20 years in a 17 ft bow rider, very durable, economical, and easy to work on. Enjoy it for what it is. I do miss the $50 fill ups...
 
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