These heads are going on an olds 403 and im wondering what the flow #'s would need to be to support 500 hp 500ft/lbs torque? Is it even possible?

 

If you have the right overall combination of parts and you port, polish and install larger valves in them it's definitley doable.

 

I have the 2.075 intake valves and 1.710 exhaust valves. 3 angle valve job and bowls ported. roller rockers and the springs are 115@1.700/335@1.150. I shaved off alot of metal. I was told polishing the intake ports are bad so i have to go back in and rough them up a little. im looking to have them flow tested soon.

 

Can you give more details on the build and goals? Why 500 hp? Are you hunting an ET?

 

If you have to rough anything up do the port floor first. That's the most important. But definitely polish the chambers if possible.

What cam are you using, flat tappet or roller?

Could've used a 2.10 Chevy intake and 1.66 Pontiac exhaust with a much better choice of springs.

 

whats wrong with the springs? im using a hydraulic roller cam.

 

Heaps o port n polish threads on net and yet to c one which recommends polishing the intakes .So ur correct.You will have to make the air a more turbulent flow. Apparently even a small rough patch in the correct part of the intake can achieve this .I would imagine the short side radius area(but check with some of the guys here )
mike

 

Nothing really just asking for more info.

 

ive decided to go with 455 c heads. now i need to sell these 7a's

 

How much for the heads? and where are you located?

 

$400. im in clinton, wisconsin

 

http://72.22.90.30/phpBB2/viewtopic.php?t=40905
http://72.22.90.30/phpBB2/viewtopic.php?t=56537
http://72.22.90.30/phpBB2/viewtopic.php?t=44013

 

heads are sold