Best heads for 550hp, 5,500rpm 502

[ECeptor]

New job and associated increase in boat budget has me planning....
So, assume 9.5:1 compression on a bullet-proof all forged 502 bottom end. Assume large single plane intake with 1000cfm carb.
What heads do you the best bang for the buck?
What if my goal was 600hp at 6,000rpm? Then what heads?

[SmokinLowriderSS]

I'm still thinking a set of large oval port, open chamber'd ones that have been ported and the larger valve set put in is the way to go. That job on my '049 heads is gonna run me a bit over $1000 next winter, depending on valve $$$$ spent. I'll be looking at right at 500 HP at 5500 and 500 Ft-pounds on an 8.5:1 454.
My setup reads about 518 at 5500 with 550 lb/ft torque in a 502 on headers. Will need more cam for an honest 550 or 600HP I feel.

[FASTRAT]

alot of people i know like the Canfield alum heads...ck with Steelcomp, River Dave, Busby & others...they can steer u in the rite direction
just my .02 cents
fastrat

[Party Cat]

I'm running a set of Dart Pro 1's...
509 cu in.
Crane 741 Hyd Roller cam
Single Holley 830
628 hp@5500 rpm
652 tq@4200 rpm (I think)
running 91 octane pump gas...
2 yrs over 100 hrs on the motor...no problems....
Tom @ Pro Marine in Havasu put it together....

[lilrick]

cast iron oval ports. big valves are a must. 049,781 on gm head or the oval port merlins which already have big valves.

[Beer-30]

Check out this thread. No since doubling up. Most of the starting info you are looking for is right here:
http://www2.***boat.com/forums/showthread.php?t=95385&highlight=502

[Carnivalride]

New job and associated increase in boat budget has me planning....
So, assume 9.5:1 compression on a bullet-proof all forged 502 bottom end. Assume large single plane intake with 1000cfm carb.
What heads do you the best bang for the buck?
What if my goal was 600hp at 6,000rpm? Then what heads?
For your application I'd research these:
AFR 315 CNC ported
Canfield 310
AFR 305
(since these are all aluminum I'd go up to 9.75-10:1 on the compression too)
Go back and check the thread on Steelcomp's build up with the Canfields. Why not a 540 Ed? Or are you planning to start with a GM 502 short block?

[ECeptor]

Go back and check the thread on Steelcomp's build up with the Canfields. Why not a 540 Ed? Or are you planning to start with a GM 502 short block?
I'll check out that thread.
I'd do a 502 because of the potential to go to a 540 in the future. The 502's increased torque will shorten the life of my B1 vs my current 330hp 454 plenty so the 540 would just be overkill. I'd get the 502 over a 454 because of the possibility to increase to 540 in the future plus the resale value it adds.
502 crate wouldn't be a bad starting point...

[Carnivalride]

Ed,
Remember if your piecing it together the in aftermarket cranks the 4" & 4.25" strokes are about the same price. Also you can use the same rods put you'll have to by new pistons too (because of the wrist pin height change). Also the extra cubes may/will change your head & cam selections. So in short it would be cheaper to build the 540 upfront and detune it than to go back and upgrade to it later.
Just my opinion,
Loren

[cstraub]

ECeptor,
I would look at the ZZ502 and just marinize it. I've got a customer that I had some porting work done, air gap intakes, and cammed the engines that will have some dyno numbers in the future off of Tyler Crocketts dyno. The Ovals on that engine have decent numbers out of the box but they do respond to work very well. The picked up almost 30 cfm after porting. I expect the engines to make a sold 560HP with a small cam.
I think SDPC man had a deal on one of these in kit form.

[502schiada]

Im running a gen vi 502 with 049 heads ported polished, 3 angles ,285# on the seat 600" solid roller, blue printed by clay smith 9.5:1 comp running 550 hp. Did very nice head work.

[Lightning]

New job and associated increase in boat budget has me planning....
So, assume 9.5:1 compression on a bullet-proof all forged 502 bottom end. Assume large single plane intake with 1000cfm carb.
What heads do you the best bang for the buck?
What if my goal was 600hp at 6,000rpm? Then what heads?
I did a similar setup and I am running Merlin heads.

[cyclone]

New job and associated increase in boat budget has me planning....
So, assume 9.5:1 compression on a bullet-proof all forged 502 bottom end. Assume large single plane intake with 1000cfm carb.
What heads do you the best bang for the buck?
What if my goal was 600hp at 6,000rpm? Then what heads?
i took a ZGm Z502 crate engine, swapped out the factory gm aluminum heads for a set of AFR CNC315's that were milled down to 110cc chambers. This gave the engine 9.6:1 cr (close to stock). With an Edelbrock Victor RPM Air Gap intake, a Holley 950 hp series carb and a Comp Cams hydraulic roller cam and valvetrain this motor made 738 hp on the dyno. It ran bitchin in my jet boat. If you pm Vicfb, he's got the cam specs because he's got the cam i used. Anyways, this is a great bolt on combo that makes awesome power.

[78Eliminator]

New job and associated increase in boat budget has me planning....
So, assume 9.5:1 compression on a bullet-proof all forged 502 bottom end. Assume large single plane intake with 1000cfm carb.
What heads do you the best bang for the buck?
What if my goal was 600hp at 6,000rpm? Then what heads?
One of the best places you could get this question answered, would be a head manufacturer like Brodix and tell them what you plan on doing. Tell them about your setup and they will most certainly point you in the right direction. Brodix also has specifications and applications on line. Just wouldn't want you to get spun into the wrong direction. Do your research, plan wisely and really have game plan.
http://www.brodix.com/