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Other upgrades to a 502.

I will be updating my stock 502 with a pro-charger m3 supercharger kit. I wanted to see what else I should do while motor is out. I will be doing rings, bearings and a freshen up.

would you recommend anything else while the motor is out? If so let me know want to make sure it’s done right and maximize my opportunity.

thank you.

cam, lifters, double roller timing chain, head studs, rocker arms, rocker studs, valve springs, retainers, locks,pushrods, oil lines, oil cooler, oil block and filter adapters, fuel pump, fuel lines, regulator, coupler, oil pan (if your going to stay in it more tahn 20 or 30 seconds at a time), better valves, upgrade to 60 lb injectors unless your not running alot of boost (5 to 6 lbs), upgrade to mefi4 IF your going to run more than 150 kpa/7.25 lbs of boost, few things that come to mind, Smitty

Main studs, align hone, harmonic balancer, pistons and rods if your going to push it real hard

That should just about cover it ......................^^^^^^^^^^^^^^....lol

perfect! Thanks for info will look at getting these parts. Thanks for the info!

Quote:

Originally Posted by articfriends (Post 4716806)

mare the rods and pistons forged already? Is there a strength difference or what should I be worried about?

Quote:

Originally Posted by articfriends (Post 4716807)

Main studs, align hone, harmonic balancer, pistons and rods if your going to push it real hard

Would it not be better to change to holly sniper efi kit then the mefi 4? More intake air and then just tune in dyno while motor is out?

Quote:

Originally Posted by Ufoman420 (Post 4716850)

mare the rods and pistons forged already? Is there a strength difference or what should I be worried about?

When I said "push it real hard" I mean if you decide to give it 12 or 14 lbs of boost. Your stock pistons are 4032 alloy , have a mini dome. If you decide to go for full gusto on the boost, a flat top or dish piston made from 2618 is more up to the task. At that point to put better rod bolts in your rods, resize them, they would still be pressed pin, not full floaters and to convert them would start to approach the cost of new ones that are better overall, Smitty

Quote:

Originally Posted by Ufoman420 (Post 4716852)

Would it not be better to change to holly sniper efi kit then the mefi 4? More intake air and then just tune in dyno while motor is out?

If a sniper kit is in your budget it would be more user friendly when it comes to tuning , yes

Biggest question is "What's your goal"? How much HP are you wanting? How much does your boat weigh? What drive/transmission is on it? How long do you plan to run wide open at a time (15 second bursts? 45 seconds? 5 solid minutes?).
Next question is "What 502 do you have, what hours are on it"?

If you have a 390 to 420hp 502, then you can run 5 lbs of boost on a stock configuration with an intercooled M3 and expect 500-530hp.

Above 5 psi, you need stiffer valvesprings than stock, but you should already be buying new springs anyhow.
Above 5 psi and 4500 rpm you need to at least put aftermarket rod bolts into your factory rods and have them reconditioned (any time you remove/reinstall rod bolts, the big end has to be cut and resized). Staying below 4500, the factory rods are sufficient, but if you have a lot of hours on them, you may be needing to have the big ends done anyhow. Bolts are a no brainer then.

Stock exhaust valve (HD Stainless) is adequate up to 5 psi. If you go above that and plan to run hard for longer than a burst, you need to upgrade to SuperAlloy or Inconel, and your guy who does the valve job needs to leave a little bit thicker exhaust seat width to help keep the valve cool.

Since you are already planning on freshening the motor, definitely ZERO DECK the block (pistons flush with the deck surface), so you will have "squish turbulence" to help snuff out detonation spikes.

But if you want to really rock and roll, Smitty's recipe is perfect.