The Toyota R family was a series of straight-4 engines produced from 1953 through 1995. scion It was designed for longitudinal use in such vehicles as the Celica xb and Cressida. OHCversions featured a chain-driven camshaft.The 1.9 L (1897 cc) 3R family was produced from 1959 through 1968 engines xb.

When introduced it had a 7.7:1 compression ratio. engines xb In 1960 the 3R was uprated to 8:1 and the 3R-B version was offered from 1960 through 1968 with the old 7.7:1 compression ratio. engines The 3R-C was introduced to comply with Californian xb emissions laws. The 3R-LPG variant was made for the last five years xb.

• The 1.9 L (1858 cc) 8R The engine xb was produced from  engines 1968 through 1973.
• Cylinder bore was 85.9 mm (3.38 in) and stroke was 80 mm (3.15 in) with a five bearing crank.It  xb engines was also available as the 8R-D, dual SU 8R-B, EFI 8R-E, Californian-spec 8R-C and DOHC 8R-G.

It was a major departure engines for the R family. xb With a 2-valve SOHC head, it impressed xb contemporary reviewers - Road & Track praised its quietness xb and free-revving nature.The Toyota upped engines the ante again with the DOHC (but still 2-valve) 8R-G, produced from 1969 through engines 1972. From 1969 to Feb 1971 it was known as theThe 2-valve DOHC 18R-G and its variations were produced from 1973 to 1982. While most 18R-Gs had a head designed and made by Yamaha,a very few had Toyota heads. Yamaha's tuning-fork logo can be seen on the Yamaha heads. Except for xb the head and related timing  engines components, most parts were shared or interchangeable with the SOHC 18R.

In 1973, air injection was added to the Japan-marketxb  18R-GR for improved emissions. A fuel injectedJapan-market version, the 18R-GEU, was produced from 1978 through 1982.Competition versions of the 18R-G and -GE include those used in rally Celicas of the period. Some of these engines had 4-valve heads and developed up to 240 HP (180 kW) of power.