need help picking intake runner size on 327 heads...

[CMars45000]

I am building a hot rod 327 for my 71 swb and I am having a tough time deciding between 180cc or 200cc intake runners on the Brodix IK-series heads...

I will be running a solid roller comp XR286R cam...the cam has has an RPM range of about 3000 to 7000 rpm...based on your experience, what runner would be best suited to this engine... oh, 11.2:1 compression with 2.02/1.60 valves...

thanks

[jamon8]

has everything to do with how much air you need

with a 327 unless its blown you should be more than ok with the 180's

[Myself]

I'm not sure what type of intake and carb tour running, I will assume high rise single plane or tunnel ram. I'd say with heavy breathing in that RPM range go with the 200's.

[57sailplane]

i ran your 327 on my calculator..

asuming your runing 100% volumetric efficiency you will pull about 215 cfm at 28 lbs..

asuming your runing 120% vol. eff.. you will pull about 245 cfm at 28 lbs..

according to brodix and there flow charts the 180s flow 245 at .600 lift and that should cover your 327 nicely.. if you go to the larger heads you will probably be disapointed cause it is hard enough to get 110% vol. eff.

the 180s are perfect for your engine..

just my 2 cents

[jamon8]

you make a good point

bigger is not always better

brodix heads are BAD Ash enjoy