which heads for a 408ci?

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We had W2 last year , Out of box 810 made 500hp. The INDY out of box make 542,using a lesser cam than we had for the W2 , sooo , INDY works.
 
No doubt Indy's work, however I think there is more potential in other heads properly ported. The Indy head is a good head out of the box though there are many ways to skin a cat. Our OP was only looking for 500 to 525 HP. This is achievable with much lesser heads.

On a side note why would you give up so much potential to run heads out of the box? You could have saved the dyno time money and spent it on head porting and been far ahead of the game.

Don't get me wrong, dyno's are great tools for those who need them. Engine builders, Pro Stock, Comp Elim, Super Stock, and Stock racers I can see. But the average drag racer really has no use for a dyno as they are not looking for that last .001 of a second. If you can use drag strip ET's or MPH in paper calculations than you can evaluate the validity of changes made.

Just my $.02
 
Glones; More potential out of the Edelbrock heads?
 
No, the Eddy's don't offer more potential than the Indy's for sure, however there are other heads out there, W5's, W7's, W8's, and W9's. Not to mention the B1 and Brodix MC heads along with the large port Commandos (which are my personal choice for new castings for use with W2/W5 valve gear.

The OP's original requirements do not need any of this more exotic stuff though. He can achieve 520 HP from a 400 cube small block with heads that flow far less than these. My suggestion is to do it in aluminum as it takes weight off the front end and you can run more compression on pump gas.

MP aluminum Magnum R/T's will do the trick with mild porting and you can run a smaller cam and use cheaper Chevy 1.6 roller rockers. It's a win/win situation. Just be sure you are going to be satisfied at that power level to make it worthwhile. Otherwise buy heads with better potential to start with.
 
OOOOOOoo, OK.
I like the BP Comando's myself. Nice I stuff think.
 
They are pretty much a W5 head without the raised and extended intake port. So you don't need the china wall spacers or special intake. The actual potential flow didn't suffer all that much either and may have even gained some lower lift flow. The W5's require some work to match the rest of the combo to the heads, or it may even be more accurate to describe it as crutching some portions of the combo because the port volume is so large low speed flow is seriously comprimised.
 
Got the 318 heads to flow a max of 214cfm at .700lift 209cfm at .600 and 206cfm at .500 lift. I got these numbers with fully ported bowls and tear droped it around the guide and some short turn radius work. haven't even touched the runner yet It flowed 177cfm stock max at .500lift. Haven't gasket matched it yet I good still or done anything to runner openings all stock runner. this is with the 1.78 intake valve still.
 
That very good for what you have done so far, and theres still about 16 more cfm's waiting yet. And by keeping the small valve the velocity will be very strong and work very well. What is the cc's of your port runner?
 
haven't checked that yet. But the venturi in the bowl is 88% of the valve diameter. They say if you go to much the air will just it the back of the valve. I will try to get a picture of it posted up. sometime today. It is ported quieted a bit in the bowl area its not just a bowl blend it is like a full pocket port.
 
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