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-   -   Advice on where to start rebuilding 5.7s. (https://www.offshoreonly.com/forums/general-q/362791-advice-where-start-rebuilding-5-7s.html)

The Sheikh 09-04-2019 10:48 AM

Advice on where to start rebuilding 5.7s.
 
Hello!

I have an 87 Formula 272 SR1 that is running twin 350 Mags.

They start and run okay, but the boat has 800 hours on it and they feel a little sluggish. I would like to rebuild them and make a little more power, while keeping them very dependable.

Is there a specific website, vendor or area of the forum that can help me pick the most appropriate parts for my application>

I would prefer not to just throw money at her, as she needs upholstery and a few other things as well, and I can't get too crazy at the moment.

Reusing what I can, upgrading where I am able and just generally freshening up is the goal.

I will need to find out which engines i have specifically, I assume. Could use some help ID'ing them as well.

Thanks very much in advance!

John

BUP 09-04-2019 10:36 PM

Prob your heads will need to be done so with that said I would look at some better heads and an Intake manifold. - Im taking it you have carb engines because of the year ??

Next would be exhaust and cam and a better carb option. Something better than straight out of the box carb.

Griff 09-05-2019 12:58 AM

First thing to do is determine if they actually need rebuilds by doing compression and leak down tests.

If they do, then start with a budget and have another 50% of that budget in reserve for the unexpected.

David Stotz 09-05-2019 03:43 PM

What Griff said

Tartilla 09-27-2019 12:54 PM

If you happen to need head work, then aftermarket iron heads can be a very economical option.

If you end up rebuilding, then consider going with a 383 by stroking the 350s.

Focus on bottom end reliability, and everything else can be upgraded later if you need to extend your budget plan into the future.

A healthy 383 with even a mild cam will get some good performance.

Since you are into the engine at that point, you can plan it out so that peak power and max RPM are above 5000. Let the engine breathe a little. 5500 max rpm should be ok for most drives. If you are making more power, then the props may be able to pull you up to the higher rpm, but factor in a prop upgrade into the budget.


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