The HiPo engine was engineered to increase performance and high-RPM reliability over standard 289 fare. It had solid lifters with hotter cam timing; 10.5:1 compression; a dual point, centrifugal advance distributor; smaller combustion chamber heads with cast spring cups and screw-in studs; low-restriction exhaust manifolds; and a bigger, manual-choke 595 CFM carburetor (the standard 289-4V was 480 CFM). The water pump, fuel pump, and alternator/generator pulleys were altered, fewer vanes, extra spring, and larger diameter, respectively; to help handle the higher engine speeds. Even the HiPo's fan was unique. Bottom-end improvements included a flaw-free selected standard block, thicker main bearing caps and crankshaft damper/balancer, larger-diameter rod bolts, a crankshaft made from 80% nodular iron as opposed to the regular items at 40%, all were checked for correct 'nodularity' by polishing an area of the rear counterweight and comparing that surface using a magnification arrangement against a picture datum, increased crankshaft counterweighting to compensate for the heavier connecting rod big ends, the increased external counter weighting at the front was split between the crankshaft damper and a supplementary counterweight place adjacent to the front main bearing journal (all designed to reduce the 'bending moment' in the crankshaft at high-rpm), all for high-rpm reliability. The HiPo equipped with a single 4-barrel Autolite 4100 carburetor carried SAE gross ratings of at 6,000 rpm and at 3,400 rpm.