Josh Carr

I'm building up a 502 for my 23' Powerplay. It started life as a ZZ502 (still have that cam). I am using Revolution marine manifolds, silent choice and open tips out transom. I want to end up with no or very little reversion and need a recommendation on cams. I know many have "got away" with using the ZZ502 cam, but others for some reason have reported severe reversion issues. I want to stick with around a 500hp package, the zz cam is exaclty the power I need, just a littl skeered to use it, whats a good SAFE alternative? Would a comp cams XM 01-451-8 be better for reversion. Specs are:284/290 adv. duration, 230/236 @.050", .547" lift w/112 center. I know the center is wider than the 110 that comes in the zz motor, but the duration is higher? May still cause reversion with wet exhaust?

ps, dry exhaust is not an option I'm afraid ;(

thanks guys

Kidnova

Must be the OSO guys are sleeping late today

ZZ502 cam worked like a charm in my ZZ for 4 seasons. But as long as you're into it, I'd suggest you contact rmbuilder. I believe he knows a thing or two about cams . And I believe there are a few here that would agree

1BIGJIM

The comp cams XM 01-451-8 be better for reversion. Specs are:284/290 adv. duration, 230/236 @.050", .547" lift w/112 center
Is this a roller cam?

Yes I would spend the extra cash and contact RMBUILDER
He ground mine and its a perfect time of year to order one before the spring rush.

Josh Carr

I may give RM a call, but I was hoping to find a comp, crane, isky, howards cam number that I can just purchase without a custom grind. That comp 451 looked decent by the numbers, just didn't know if the 112 LSA was safe enough. Seems like most post I have read came to conclusions that 114 was the best bet (I know it's more that just LSA that causes it though).

Josh Carr

Oh, yep it's a roller. That's the other thing.... I want to stick the the gm roller lifters if possible which means keeping lift under about .570".

KAAMA

"RMBuilder"/Bob Madara only charges about $70 over what you would normally pay for an "off the shelf" cam----not too bad for a consulting fee.

Josh Carr

That's not a bad deal... I did come across a cam that sounds good to me on Keirh Eickert's site: Hardin/Comp cam Hyd. roller 284/284 duration, 224/[email protected]", .566" 112 LSA. Less duration on exhaust than the ZZ502 cam and 112 instead of 110 LSA, but with slighlty more lift. I would think this would be similar power to the zz502 cam but less chance of reversion.

Noise Pollution

If its a Gen VI block
Crane Cam
part # 168741
610 lift intake
630 exhaust
Lsa 112
I'm running Eddie Marine wet exhaust. No reversion

website with all specs

http://cranecams.com/index.php?show=...41&lvl=2&prt=5

Airpacker

Lemme take a guess here. I ran the exact same boat with a zz502 short block, merlin rec port heads with some mild port and bowl work, a 741 crane cam, victor jr intake and a 1050 dominator with more hours work in it than I care to remember, SM Dominator exhaust, Bravo 1 with a Mirage plus 25" prop and hit 68mph light.

If your aiming for 70mph, you will need more HP than the basic combo I described.

Now, if you build a 540 with basically the smae setup, you can hit 72.

I gave up and bought a cat

Smitty

I've got a Crane 731 roller cam for sale.It is for a Gen VI block. It has less than 100 hrs on it. It made great power on my 502 motor. It will slide right in and you can re-use the stock lifters. I would like to get 275.00 for it. They sell new for 435.00 at Summit. The lift is 587 int and 610 ex and a 114 center. PM me if interested. I have 2 to sell.

Smitty