470 low deck 11.3 comp,.586 solid lifter 286 dur,259@.050,pro maxx 78 cc heads,hs 1.5 rockers,383 victor or m-1 intake,2"headman headers.if not what changes need made.thanks,Sam,

Which heads and port sizes?

Yes and what do the heads flow ? Ron

You need more than 300 cfm flow to make 600 hp. I haven't ever seen a set of ProMaxx heads but Jeg's says they flow 295 cfm. So you might get close to 600 hp but I doubt you're going to crack it with that combo.

I doubt it either, my mate ran a 12.7:1 domed JE piston 440, MC Eddy heads 320cfm, DC.590 solid, Victor intake and 1050 Dommy w/2" hdrs, track hp worked out to 588 on his best 10.1@131mph/3150 weight, this wasn't a "fresh" motor though, might've picked up a bit with a re-ring. I personally thought it was a bit under cammed and could've gone in the 9's with my old CC.650", 290@.050 solid I used to run.

Out of the box, or w/ a basic bowl blend? No.

With some fairly extensive port work? Probably, with the right tuning of the rest of the combination.

You don't mention the intended carb, either, which could be another limitation.

the bowls on these heads look really good compared to eddys,the casting looks smoother and bowl looks better designed.I did gasket match the intake ports.carb is a quick fuel 850 race carb.

Some of you guys calculate your flow to horsepower improperly . Let's assume your heads flow 310 cfm at .700 lift or .750 but you are only running a 590 lift cam. Now let's subtract lash and deflection and we are now down to .555 lift or possibly less. Now what are your flow numbers for the split second that you are at .555 max lift. I'll tell you this, you are nowhere near 310 cfm

I have a 512 with promax heads - 11.2/1 compression. I dynoed last week at 608 hp and 649 torque. Heads are cnc flowing 335. Cam is 260 @ .050. Roller rockers with 1.5 to 1 ratio. Cam is a solid flat tappet and intake is a 6 pack port matched to the heads and ported. I think you may be a little short with a 470 cubic inch motor.

If the short block prep is "right", I actually think it would be pretty close.
Might need to massage that intake a little.

rat on!

I think you are down 40 or more HP from where what you described should make. What are you running for headers? Or maybe even "ported" a 6bbl intake is holding it back.

Yes 6-pack is holding me back. I was thinking this combo would have given me 650 however I wanted to stay with the 6-pack intake. It is an original A-12 set up with aluminum manifold and vacuum pods on the end carbs. The numbers were with 2 inch dyno headers. We lost a little with 1 7/8 headers for a few pulls after that. Can't remember what we had I will have to check the dyno sheets.

thanks for the feed back guys,i will put in the car and see what I get.

This discussion begs the question, how accurate are the published formulas based on ET, MPH and weight. I've always accepted the results as valid, but are they??

should this make 600 hp?

Yes.

x2.....spot on!

I think you could use more carb...............

It couldn't be that simple, a few questions if you will.....What was the cams lift? What did the 6 pack intake flow as there notorious for core shift. What did you do too the carbs? Swap in a 4412 for the center carb?

Cam lift is .600. Carbs all original with 66 Main Jet in Center and 82 end. Promax metering plates on the end carbs. Yellow springs. Never flowed the intake.