dart 335's cnc would be a nice choice.

my .02
DAVE

I would get the cnc versions. And get them bare. I didnt do either and ended up doing all of the above work anyway! Hand porting was about 20 hours and they are not exact, you dont get inconel valves and wider valve seats. 325-335 for 502. They will still work good on a naturall aspirated 540 and make a ton of torque. Greg

Greg ,,,above is right ,,,Blown 1500 or I can save you money on A F R heads ,brodix or darts ir you want ,,,just p.m. us ,,,c,n,c, .....is the way to go

looking for brodix bb2 plus with 100cc chamber who much bare
cnd and no cnc thanks

Has anyone got specs on the Big Chief 14 degree oval ports?

thanks

Dick

If you are running a supercharger you will be wasting your money buying heads. Just use the stock rectangle port heads, they will flow all the air you need. The blower will push plenty through them! They have 320 cc intake ports and big combustion chambers. Buy some blower pistons instead, so you can pump up the boost without worry!
Sincerely
Dennis Moore

Dennis Moore,,
That is definately the best advice given.

I dissagree. For comparison the stock GM exhaust ports flow less air than a ported A/M small block chevy head. In a situation like this you will end up with higher boost pressure. My 540 made over 900hp with A/M aluminum heads hydraulic roller cam 8lbs of boost 92 fuel. Dennis, do you honestly think that could be done with stock GM heads?

I was told that with better flowing heads, that the HP will increase. I was also told the boost will drop a little, but I could increase the boost with a different pulley and make even more HP. This does make sense to me.

What are your thoughts JimV???

29 scarab

Thats correct. Lets you have a stock set of GM heads with 6 lbs of boost making 600hp. You have your heads ported and increase airflow 20%. The hp numbers will increase to 650 and the boost will drop by 2 lbs. You then change pulleys to get back 6lbs and gain another 30-40 hp. (The numbers may not be correct but you get the idea)