I put a low deck (400 block) 6 pack pump gas stroker motor together using a stock unported Eddy low deck six pack intake with stock type 440 carbs, the motor was 517 C.I. (4.375 bore x 4.300 stroke) with 10.29 to 1 compression with a set of Eddy RPM heads CNC ported by MCH, Comp Cams custom ground solid roller cam that was 260@.050 on the intake with .420 lobe lift and 266 @.050 on the exhaust with .409 lobe lift, Harland Sharp 1.65 ratio roller rockers that netted .700 at the retainers with checking springs.
This motor combination ran a bunch of 10.30 at 127.6 MPH through the 3.0 inch exhaust system on with a stock 6 pack air cleaner with dual stacked stock 6 pack Fram air cleaner elements in my 1971 Duster that weighed 3450 lbs. with me in it
IHTHs