440-1 heads originally ported by Radar at R & J from Cedarfalls Iowa. VERY pleased with the power they made originally, but got greedy and tried to improve on the original work with 2.3 valves.
Of the two plots on the chart, the lower flow plot was with 2.25 valves, one with 2.30 valves and exhaust reduced to 1.78 to make room for them. Didn't show a bit of power improvement with the bigger valves, so I may send them back to R & J and see what they can do, if anything to make use of the extra flow.