at 2,400 rpm, respectively. In 1968, the two-barrel was reduced to . A-Code In 1965 the four-barrel version was increased to 10.0:1 compression, and was rated at at 4,800 rpm and at 3,200 rpm. The 289-4V was also the engine for the first Australian Ford Falcon GT, the XR Falcon GT. Production Numbers Around 3,500,000 289-2V and 289-4V engines were made at Cleveland Engine Plant 1 (CEP1) in 1963-1967 and 800,000 289-2V at Windsor Engine Plant 1 (WEP1). 289 HiPo (K-code) A high-performance version of the Challenger 289 engine was introduced late in the 1963 model year as a special order for Ford Fairlanes. The engine is informally known as the HiPo or the K-code' (after the engine letter used in the VIN of cars so equipped). Oddly, this engine was introduced in 1963 as the only 289 engine available in the intermediate Fairlanes. Lesser-powered cars had the 260 engine in that year. Starting in June 1964, it became an option for the Mustang. 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. The K-code HiPo engine was an expensive option and its popularity was