meant to accept an AFB 4-barrel Carter Carburetor, the AFB carburetor itself and an appropriate air cleaner, dual (front-3 and rear-3) cast-iron exhaust headers, a large-diameter exhaust Y-pipe to connect to these dual cast-iron headers, a larger muffler, a 276°-duration camshaft with appropriate valve springs and pushrods, a heavier-duty clutch, a manual choke control, a starter motor modification template and, in the full-race version of the package, high-compression pistons designed to increase the engine's compression ratio to 10.5 from the stock 8.5. The Hyper Pak was recommended for installation only on vehicles equipped with manual transmissions, for the camshaft was of such characteristics that a high idle speed was required to prevent engine stall-out. The Hyper Pak was primarily intended for competition driving, its road manners involving rough idling and poor cold-engine driveability, a high power band and poor fuel economy. In competition events it proved unbeatable. Seven factory-backed Valiants entered the 1960 NASCAR compact car race at Daytona Beach, and humbled the competition. The Valiants came in first through seventh. A high-fidelity reproduction of the Hyper Pak intake manifold was created by Slant-6 builder Doug Dutra in the late 1990s. Subsequently the tooling was sold to a marketer of performance equipment (Clifford Research, 6=8) for inline six-cylinder engines. Multiple carburetors For the 1965–1968 model years, Chrysler Argentina equipped Valiant GT models with a system of dual 1-barrel Holley RX 7000 A carburetors and other engine specification changes. Claimed output was , compared to the single-carburetor version of the engine producing 2-barrel carburetion Export 2-barrel setup For the 1967 model year, a 2-barrel carburetor setup was released for export production. This configuration, similar to that found on marine G-engines beginning in 1965, consisted of an iron intake manifold with open-plenum 2-barrel carburetor mounting pad, a Carter BBD carburetor, and associated air cleaner, linkage and plumbing changes. Also installed on these export 2-barrel engines was a slightly hotter camshaft (244° duration rather than 240°), and a distributor with modified advance curves. This engine, rated at , was popular in Central and South America, South Africa, Australia and New Zealand. Driveability characteristics were generally superior to those of the 1-barrel engine, but to avoid cutting into sales of the more expensive V8 engine, this 2-barrel setup was not offered in the North American market. Of particular note is the automatic choke design found in this export 2-barrel setup. Most Chrysler products used