I am upgradeing a gen 6 502 410HP to a little over 500HP. What I am wondering is should I spend the money upgrading the stock heads ( seats ,springs,valves,studs ect. + some porting on the bowls ) or should I buy a set of used HP 500 heads and add new springs. the money is about the same. Is there any performance benifits to the HP 500 casting over the stock casting. any advice would be helpfull. the season is approaching.

If I were you I would upgrade your stock heads. From what I understand the 500Hp heads and the regular 502 heads are the exact same casting. I think you'd be better off doing the upgrades that you mentioned above, and at least then you know what you're getting (you know that they're brand new, you don't have to take someone's word for it that they only have 30 hours on them), and you walk away with ported heads...

That said, you might want to ditch the idea altogether, buy a set of bare casting aluminums, and put your valve train on them... It really shouldn't cost much more, and you should get more out of them than ported 502 heads, not to mention the weight savings, and ability to increase your compression ratio. This move also allows you to sell your old 502 heads for a couple of hundred bux, or save them and put them back on when you go to sell your boat.

Great point,any advice on after market heads?

Rebuild the heads you have. You should talk to Bob RMbuilder, he can set you up with a Roller cam and matched components. I have a 489 stroker with large oval GM heads and custom roller. I run well over 500HP with a good idle.

Dart and Brodix seem to be the most popular. Edelbrock seems to have the cheapest castings, and still seems to provide good results... It all depends on how much $$$ you want to spend. I think a new set of Edelbrock castings is around $925 or so, and I've seen them used for $750. If you want to stay cheap you might want to look for a set of them. If you have a little more coin to spend you'd probably want the Dart Pro 1s.

I think for the sake of budget, I'll take your advice and put the money in good components on current castings then get bare castings on next winters upgrade and swap over components.Any opinion on replacing the current seats.I've budgeted to replace them but does it really improve my chances of none failure.

You may want to consider the alum. heads now. Pretty much whatever hardware you buy for the stock steel heads will not be able to be used on the alum. heads. They will take different valves, springs, retainers, locks, seals, rocker studs, etc. If you are going to replace all of the hardware on the stock heads, then it wouldn't cost any more to buy that same hardware for alum. heads. It is all the same price, just different parts. So, at that point, alum heads will only additionally cost you the price of the bare heads. Depending on the brand of head, that will be from $1200-1700. If you rebuild the steel heads now and want to upgrade to alum. next year, then you will have to buy all the hardware again. This stuff is expensive enough without having to buy it twice. Just something to keep in mind. Let me know if I can help.
Eddie

A guy in the Swap Shop has some brand new Dart Pro1 heads for $1,475. There is another guy telling him he can buy new ones from Cobra Power for $1250. I am not sure what is the right answer, but if you take what you are planning on spending on your heads off the price of these they look like cheap HP.

Check out the new AFR 290 oval ports. They are full cnc chamber, intake and exhaust runner, the valves are back cut.. These will out flow just about every other head under 315 you really can't find a better head for the price. Complete I believe there around $2800 or less. Call Bob Mandera, he can get you a good deal on these. If you need his number PM me. I really don't think you will find a better head for your engine! I'm doing a 439 BBC and am using the new 265 oval. I'm pretty sure my 265's flow just a little less than a stock dart pro 1 with a much smaller runner size.

My bad, the heads in the Swap Shop are bare heads.