were built in Mexico through 2000. The G-engine was used by Chrysler's international operations in locally produced vehicles. It was also purchased by other original equipment manufacturers for installation in commercial vehicles, agricultural and industrial equipment, and boats. The G-engine gained a reputation for reliability and durability. The basic design is rigid and sturdy, in part because the engine was designed to be made of either iron or aluminum. An aluminum block was produced in 1961–1963, but most blocks were made of iron. The block is of a deep-skirt design, with the crankshaft axis well above the oil pan rails for structural rigidity. Although only four main bearings are used, they are of the same dimensions as those in the 2G (1964–1971) Hemi, and fewer mains results in a crankshaft better able to withstand the effects of torque. Efficient cooling and lubrication systems, a favorable ratio of connecting rod length to stroke, and a forged steel crankshaft (on engines made through mid-1976) all contributed to the engine's strength and durability. The G-engine gave better performance than its competitors at its 1960 introduction, and generally kept up through the 1960s and early-1970s, though engines like the Pontiac OHC Six, a brief GM outlier, bested the performance of most versions of the Slant-6. After an early factory racing program was discontinued by 1962, the Slant Six did not receive much performance development. Most Slant Sixes were equipped with a single 1-barrel carburetor. Starting in the early 1970s, primitive emission controls adversely affected driveability and power, though a version of the 2-barrel carburetor package first released for marine and export markets in 1967 was offered in North America from 1977 to 1983 under the "Super Six" name. Performance figures were only slightly higher, but driveability was substantially improved. Other Chrysler engines were released with more advanced combustion chambers, electronic fuel injection, and other modern improvements, but the length of the Slant Six precluded its use in Chrysler's front-wheel-drive cars. A new V6 engine was created for the 1987 Dodge Dakota compact pickup truck by removing two cylinders from the corporate LA V8 engine. It replaced the Slant-6 in the rest of the Dodge truck line at the end of the 1987 model year. Significant production changes The combustion chamber shape was slightly modified for 1967 to promote more complete combustion and reduce exhaust emission toxicity. All G engines used forged steel crankshafts until