502 496 500hp 525 540 most reliable power
 

So I am in the market for another boat. Looking at

Fountains
29 with twins only
35-38

Baja
33-36

Im curious whats the best motor choice for what i am looking for I'm obviously not trying to be the fastest guy on the water that will never happen. I want a boat that's not under powered and is reliable as it can be.
I have been coming across many boats with refreshed 500hps but they are carb options.
Which leads me to my next question Carb vs EFI

Thanks for your time

I would say they are all equally reliable. The 502mpi and 496's should go 1000 hrs before needing any major refresh.
The 500, 525 and 540 will need top ends refreshed about every 300hrs and possibly full rebuilds every other 300hrs.

griff I’ve been meaning to ask this question…agree on need to refresh top ends on blue motors every 300 hours. the stock springs are prettty weak. Coupled with junk head gaskets…it’s probably a good idea.

what I don’t understand is rebuilding a bottom end on a 500efi at 600 hours. Everything is more stout than say a 496 and it has a lower compression ratio. Why do black motors get a 1000 hour pass but we say blue motors need a full refresh at 600?

They probably don’t. But maybe redoing your heads 3x before your rings would push oil consumption up (past the rings)

every blue motor I’ve taken apart at 450-600 hours the rings have lost a lot of tension and the cylinder walls are glazed. Pistons slide right out during disassembly.

Don't want to hijack, but if your running WOT at lot are you better off with a blue motor or a black motor 496 or what about a 6.2L in terms of reliability on a go-fast application?

arent they low tension rings anyways? if oil consumption is low or non-existent…why tear apart the lower end?

im by no means an expert but blue motors have a lot better components than a 496. forged pistons, better valve train, etc. they are built for WOT. with that being said they also require more mainentance.

as for SBC we owned them for 5-6 years. We beat the crap out of them and they kept running.

crap shoot if you ask me

i personally wouldn’t consider carb power in todays day in age. The fuel consumption alone is enough to make the decision.

with that being said fuel injection idle better, run better, etc.

Supposedly the 496 passed mercs 100hr peak tq to peak power endurance test.

I don’t really have a dog in this fight, but I do think Merc racing’s valvetrain service interval is ridiculously short. The 500efi with its milder cam seems to last a lot longer than a 525