July 19, 2006

Flow Bench
RHS shipped three Pro Action cylinder head castings to Westech in Southern California for us to demonstrate how these heads flow right out of the box. Here are the results as based on a 4.030-inch bore.

180cc Air Flow Specifications
Valve LiftIntake Flow in CFMExhaust Flow in CFM
.050 in23.420.0
.100 in55.648.0
.200 in111.098.0
.300 in158.0133.0
.400 in206.0170.0
.500 in240.0189.0
.600 in252.0198.0
.700 in260.0203.0

200cc Air Flow Specifications
Valve LiftIntake Flow in CFMExhaust Flow in CFM
.050 in31.523.0
.100 in63.050.0
.200 in119.0104.0
.300 in172.0140.0
.400 in216.0174.0
.500 in244.0193.0
.600 in264.0203.0
.700 in275.0209.0

215cc Air Flow Specifications
Valve LiftIntake Flow in CFMExhaust Flow in CFM
.050 in26.524.0
.100 in60.052.0
.200 in116.0102.0
.300 in168.0134.0
.400 in217.0172.0
.500 in260.0181.0
.600 in292.0190.0
.700 in305.0200.0