To top their 440 short-block, Promax was required to use the same Indy SR cylinder heads as the rest of the competitors. Rather than porting their heads to Max-Wedge port dimensions for maximum flow, Promax opted to keep the same port dimensions as factory 906 heads because too much port volume wouldn't match the rest of their combination. Of course the heads were treated to bowl blending, and ported to the extent possible while retaining the factory port openings, then treated to a multi-angle valve job, stainless steel valves, and new Comp Cams roller valvesprings. Harland Sharp roller rocker arms were employed to actuate the valves. For induction, Promax again would like to thank a generous customer who allowed them to use a Weiand high-flowing Six-Pack intake manifold. While most Six-Pack intake manifolds are limited by their dual-plane design, the Weiand unit has a raised open plenum, making it a better choice for peak power. To mix the air and fuel, a trio of Promax prepped Holley two-barrels were utilized. Having special metering plates allowing jet changes in the outboard carburetors, the Promax Six-Pack carbs pretty much set the standard for three deuce tuning.