502 cam specs

[junkyardhunter]

I have a marine power 502 (2001 yr).I want to know the cam specs & the rated HP.All I know is that it has REC port heads & weiand stealth intake.

[Beer-30]

I can't help you with the cam specs, but I do know you could turn it into 600+ hp real quick!
Edelbrock just did some testing on a base 502 with their new top end package:
http://www.edelbrock.com/automotive_.../2094graph.jpg

[victorfb]

most likely it has the GM part # 12551622 or merc part # 431-850478.
lift is .483 on both intake and exh.
duration @ .050 is 224 both intake and exh.
115.5 lobe seperation angle.
lobe center line 109 ATDC intake and 122 BTDC exhaust.
these specs are for the genVI hydrolic roller cam.

[jbone]

Isn't this the 415 hp version?
J

[cfm]

most likely it has the GM part # 12551622 or merc part # 431-850478.
lift is .483 on both intake and exh.
duration @ .050 is 224 both intake and exh.
115.5 lobe seperation angle.
lobe center line 109 ATDC intake and 122 BTDC exhaust.
these specs are for the genVI hydrolic roller cam.
Yup, that's what I have for Merc also. Sorry - nothing on your manufacturer.
Note: below just my notes. Don't take everything 100% in case my notes are a little messed up.
Merc Std BB Roller (oval 454)
Merc# 431-850453T / GM#12552296
.004” 280,299
.006” 266*/284*
.050” 204*/209*
.200” 113*/114*
Lift .480”/. 483”
ICL 115.5*
ECL 120.5
LSA 118*
………………
Merc Mag Roller (454/502 Mag)
Merc# 431-850478 / GM#12551622
.004 300*/ 300*
.006 288*/288*
.050” 225*/225*
.200” 125*/125*
Lift .483”/. 483”
ICL 109*
LSA 115.5*
................................
Merc HP500 Carb
Crane Gen VI#169611 Grind#HR-284-2S-10IG
Adv 284, 292 at .004” Lift with 1.7 .576 / .598
At .050” 222, 230
ICL 105, ECL 115
LSA 110
................................
Merc 500EFI
Crane Gen VI #169621 Grind#HR-292-2S-14 IG
292,298 at .004” Lift with 1.7 rocker .598” , .610”
230, 236 at .050”
ICL 109 , ECL 119
LSA 114
...............................
Merc 525 EFI
Crane #16HR00004 ?????
298º/306º @ .004"
236º/244º @.050"
.610"/.632" Lift Valve
114º LSA

[junkyardhunter]

Thanks

[cfm]

I believe this is their website : http://www.simplicity-marine.com/mpow502.htm
They show a premium 410hp 502 and a performance 450hp 502. Willing to bet the difference is in the camshaft and probably intake manifold.
As a maybe:
GMPP's (GM Performance Parts ) 450hp 502HO roller motor uses a cam GM#24502611 with 211°, 230° at .050" .510",.540" and 112° LSA. So, don't rule this one out either, especially if you have the 450hp version. Marine engine "manufacturers" use off the shelf or "already in the motor parts" a lot.

[junkyardhunter]

I just found the marine power manuel that came with my boat.looks like its 415HP