Received new Promaxx 171/65cc heads a few days ago. Promaxx recommended Fel Pro 1213 intake gasket. Measured intake ports on heads a few minutes ago at 1.125" x 2.250". Looking at using a Edlebrock RPM AirGap intake (port: 0.98" x 2.16") on website. Fel Pro 1213 port size is (1.160" x 2.270") according to website.
Head ports are larger than the intake ports and gasket ports are larger than the head ports. Gearing this build for performance street application, at least what I think of as...
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Head ports are larger than the intake ports and gasket ports are larger than the head ports. Gearing this build for performance street application, at least what I think of as...
Read more
