The Toyota Motor CorporationG-family engine is a family of straight-6 piston engines produced from 1979 to 2006. It is notable in that only a single displacement,, was produced in this series. All were belt-driven OHCnon-interference engines, with multivalveDOHC and even variable valve timing added later. The 1G-GEU was Toyota's first four-valve twincam engine. A prototype version of the 1G-GEU called the LASREα-X, featuring twin-turbos, variable valve timing and intake as well as variable displacement, was fitted to the Toyota FX-1 show car at the 1983 Tokyo Motor Show. It showcased a number of technologies which were later to become commonplace. For ten months, Toyota also offered Hino's GR100 engine as the "Toyota G" in the shortlived Briskalight truck. These engines were used as a lower-displacement alternative to the more upmarket M family and JZ family straight-sixes.
G (Hino GR100)
After Toyota's takeover of Hino, the Briska one-tonne truck was sold with Toyota badging for ten months. The engine code was changed from Hino's "GR100" to "G" for these cars. The engine is a 1251 cc watercooled OHV inline-four with distant Renault origins and was originally developed by Hino for their Contessapassenger car. Bore and stroke are, maximum power at 5500 rpm. Hino's earlier models had a variety of power outputs ranging from 52 to 65 PS.
1G
Since just one displacement was offered, all G-family engines are marked 1G and share the same "square" bore and stroke. Applications:
The Japan-spec 1G-EU was produced from 1979 through 1988. This and the 1G-E are the only two-valve SOHC members of the family. Output was at 5400 rpm and at 4400 rpm.
1G-FE
The DOHC 1G-FE uses a narrow valve angle and other fuel economy optimizations. It was introduced in 1988, it features a cast iron block with aluminum cylinder head. Output was at 5,600 rpm and at 4,400 rpm. In 1998 VVT-i was added, which bumped output to at 6,200 rpm and at 4,400 rpm for the Altezza/IS 200. With the end of the first generation Lexus IS this engine ceased production in 2005. Applications:
The 24-valve DOHC 1G-GEU was intended for high performance and featured a pent-roof combustion chamber. Introduced in August 1982 and produced through 1986, mostly for the Japanese market, output was at 6,200 rpm and at 5,600 rpm. This was Toyota's first multi-valve twincam engine to make it to the market, and won the "JSME Medal for New Technology" in 1982. To minimize the downsides of a multi-valve setup, the 1G-GEU was also equipped with T-VIS, increasing low to mid-engine speed torque. Like all following twin cam Toyotas, it used a timing belt rather than chain, for less noise and lower maintenance requirements. In August 1983, the fuel injection system was changed to EFI-D, which measures the pressure in the intake manifold to determine the proper air-fuel mixture. Applications:
The 1G-GE replaced the 1G-GEU in 1988. It was detuned from down to and served the same cars as 1G-GEU did. It was produced for the Supra GA70 until 1993.
1G-GTE
The 24-valve DOHC 1G-GTE added two CT-12 turbochargers to the versatile motor. There were 3 generations of this engine both air-to-air and air-to-water intercoolers were used, pushing output from at 6200 rpm and at 3800 rpm using the air-to-air over the air-to-water. This was the most powerful engine of the whole G family. In May 1991 it was replaced with >280 hp 1JZ-GTE on most Toyota cars. Applications:
The 1G-GZE was a supercharged version produced from 1986 till 1992. Output is at 6000 rpm and at 3600 rpm. Like the turbo, it was a 24-valve DOHC engine but featured a distributorless ignition system. The 1G-GZE was mated only with automatic gearboxes. In August 1991 it was replaced with the 1JZ-GE on the Mark II/Chaser/Cresta, while serving on the Crown until 1992. Applications:
