Head Capabilities

[Bluemach91]

Alright, some ass hat is going around saying that any B head is better than every C head. B heads flow better stock and will always flow better ported than all the c heads...

I was under the impression that the 03/04 C heads were the best heads from a flow standpoint out of the stock 4v heads. If that were the case then they could also outflow ported b heads right? He's trying to tell me that ported c heads will only flow 270 and b heads easily flow 300+...

Who is right?

 

[deadpres]

4V Cobra '96-'98 Ported TEA Alum
CFM - INTAKE/EXHAUST
305/269 @.500 Lift

4V Cobra '03-'up Ported TEA Alum
CFM - INTAKE/EXHAUST
324/263 @.500 Lift

'TEA' is Total Engine Airflow

^all flow data was pulled from this chart: http://users.erols.com/srweiss/tablehdc.htm

 

[Ry_Trapp0]

john mihovetz - the modular king, and owner of THE highest HP 4.6ls - runs B heads, pushing 2500HP. granted, that's at 60PSI and 9700RPM, but those heads are still flowing 2500PSI worth of air. airflow capability may not matter as much under boosted applications as it does under naturally aspirated engines, but if the heads can't flow then they can still cap maximum HP(each PSI of boost produces increasingly diminishing returns).

long story short - the "bad" B heads are capable of flowing more than you would ever need under boost, but 00R/GT/GT500 heads are the top of the heap in an NA application(with a custom intake manifold of course).

 

[CobraBob]

john mihovetz - the modular king, and owner of THE highest HP 4.6ls - runs B heads, pushing 2500HP. granted, that's at 60PSI and 9700RPM, but those heads are still flowing 2500PSI worth of air. airflow capability may not matter as much under boosted applications as it does under naturally aspirated engines, but if the heads can't flow then they can still cap maximum HP(each PSI of boost produces increasingly diminishing returns).

long story short - the "bad" B heads are capable of flowing more than you would ever need under boost, but 00R/GT/GT500 heads are the top of the heap in an NA application(with a custom intake manifold of course).

Good info that brings things into perspective.

 

[acdrew]

I to was questioning this and swapped to c heads for the price I paid for the swap. I could have had a set of ported b heads.