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freshening up some 502's

Old 09-07-2017, 01:30 PM
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Default freshening up some 502's

I have a pair of 502's I am looking to get freshened up and while I am at it, make a little more power.
A little history: 1993 Cigarette, it had 525SC's pretty much stock with exception to blowershop 250's instead of 177's...
swapped the 454 long blocks back in 09 with some 502's from Baker Engineering and put the old upper ends back on
Nothing fancy but have been very sound and reliable motors for several years....

In looking at refreshing these, is there any advantage to opening up the cylinders, changing crank, stroke etc?
I need a little education here... can these go to 540's or 572's? reasonably?

What are some options I should consider if I want to go beyond a top end refresh and a little more reliable HP to these?
Thanks in advance!
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Old 09-07-2017, 07:31 PM
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Ideally 540 rotating assembly and good aftermarket heads. All depends on budget. I don't see any need to go crazy on rotating assemblies and heads you could go with EQ's 320 cc int runners. Their cast but perfect for marine use and with a little work they flow well.
650-675 hp
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Old 09-08-2017, 01:23 AM
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The TBS 250's are pretty much maxed out with a 502ci, especially with the single 1050 carbs.
Maybe bore them to 509's if needed, but that's as far as I'd go. I'm guessing you are 600ish Hp now, and adding more with Bravo's is asking for drive issues.
I know it would run 74mph when Mike had it and at about 550hp. How many mph did you pick up when you went to the 502's??
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Old 09-08-2017, 08:39 AM
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when you start to put price numbers on things like stroker kits and better heads you might decide to freshen up what you already have and go boating.
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Old 09-08-2017, 10:01 AM
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If you're only looking for a little more hp, what does it have for a cam now ? If you don't know, let's find out.
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Old 09-08-2017, 10:16 AM
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Originally Posted by mike tkach
when you start to put price numbers on things like stroker kits and better heads you might decide to freshen up what you already have and go boating.
I'm pretty sure that 99% of boaters that moved away from the stock setup wished they listened to this advice.
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