The Toyota R and T-series Engine Guide

 

Toyota is famous for its high revving and high power twin-cam engines. In this article we look at the first DOHC Toyota performance fours from the R and T-series designs. These are true classic engines that, even by today’s standards, make respectable power – those that aren’t choked by emission equipment anyway...

R-series Engines

One of Toyota’s earliest four cylinder engines (and the longest lived) is the R-series, which was released way back in the 1950s.

The R-series is an in-line four configured for longitudinal mounting and rear-wheel-drive. The first in the series was the Toyota R spanning from 1953 to 1963. This engine has a displacement of 1453cc and breathes through either a pushrod or SOHC valvetrain and simple downdraught carburettor. The R engine then progressed through a series of incarnations until a DOHC, two-valve-per-cylinder head was adopted in almost all models during 1972. However, predating this are the DOHC 9R and 8R-G which were available from ’67 to ’72 – these engines displace 1.6 and 1.9 litres respectively and were reserved for go-fast Corolla and Corona models. The big 1.9-litre 8R-G runs a 9.7:1 compression ratio and puts out a then-impressive 104kW at 6400 rpm.

The first mainstream DOHC R-series engine was the 18R-G of 1972. The 18R engine displaces 2-litres using a 88.5mm bore and 80mm stroke. The early 18R-G runs a 9.7:1 compression ratio, twin side-draught carbs and a Yamaha designed DOHC, two-valve-per-cylinder head to help generate 108kW at 6400 rpm. This engine can be found in Japanese spec Corona models.

But there are plenty of other versions to confuse things!

A low emissions version, the 8.3:1 compression 18R-GU, was released in ’75 making 11kW less. Then, an L-Jetronic type EFI version, the 18R-GEU, appeared in ’78 and it appears there are two incarnations – one making 90kW and another making 101kW. An ‘air injection’ version, the 18R-GR, also appeared in the early/mid ‘70s making 104kW.

As emission standards continued to tighten, the 18R suffered further power losses. The late ‘70s 18R-GR slipped to 97kW, the EFI 18R-GEU came in at 93kW and the ‘air injection’ 18R-GU made 90kW neat. The base 1980 spec 18R-G is rated at less than 90kW...

Curiously, DOHC breathing was not applied to any other R-series engine despite its continued use well into the 1990s. Instead, you’ll find an increasing number of cubes.

From the late ‘70s to the late ‘80s, Toyota produced a new generation 2-litre 21R engine. In its most strangled guise (the ‘80s Californian-spec 21R-C), this engine struggles to generate 67kW. Other versions, the 21R and 21R-U, make around 78kW. It appears that all versions of the 21R use a single downdraught carb. Bigger still is the 20R engine used between the mid 1970s and 1980. The 20R engine (essentially a stroked 18R) sweeps 2.2-litres but, unfortunately, the most powerful version can muster a lowly 72kW. The original 18R-G (with its smaller capacity) is f-a-r more desirable. The 20R engine is most commonly found in the boxy style Corona and Celica.

The biggest member of the Toyota R series engine family is the 22R. The 22R was first seen in around 1980 under the nose of Hilux, Celica and Corona. With a 92mm bore and 89mm stroke, the 22R displaces 2.4-litres and, again, breathes through a SOHC head. Output of the single carb models is typically around 72kW but the EFI version, the 22R-E, makes an extra 6kW. In 1990, the engine was updated and the base 22R was elevated slightly to 80kW while the 22R-E makes 84kW.

Take a look under the bonnet of post ’84 Hilux and you may find a turbocharged version of the big 22R – the 22R-TE. With the compression ratio slashed to around 7.5:1 and given around 7 psi boost, the 22R-TE generates a healthy torque but a mild 101kW at just 4800 rpm.

T-series Engines

Released in 1970, the Toyota T-series four uses some similar design cues to the R-series but is more compact and is found in a range of smaller vehicles. Again, the engine is designed for longitudinal mounting and most early versions use a single downdraught carburetor. The block is cast iron and the head is made from aluminium.

The first real performance version to use a Yamaha-developed DOHC head is the 2T-G 1600cc of the early ‘70s. With a 9.8:1 compression ratio and twin side-draught carbs, the 2T-G pumps out 86kW. From 1974, the Euro-spec 2T-G was upped to 93kW. This engine was equipped with a five-speed manual in the original A20 Celica 1600GT and E20-60 series Corolla Levin 1600GT.

Again, as emission standards clamped down, engine output plummeted. As air injection and lower compression ratios were adopted, output fell to around 82kW. Like its 18R-G cousin, the once famed 2T was watered down until it was almost irrelevant in the market.

The 2T was then aced by the 3T engine with its larger 78mm stroke achieving a 1.8-litre swept capacity. Most examples of the 3T are pretty pedestrian in design and output but the 1982 released 3T-GTEU is an exception. The 3T-GTEU uses a DOHC, two-valve-per-cylinder head, twin spark plugs per cylinder and a single CT20 turbocharger to boost the 7.8:1 static compression ratio. Boost pressure is set to around 7 psi and there is no intercooler. This engine was at the pointy end of four-cylinder performance with its 120kW/207Nm output. The 3T-GTEU can be found in rear-wheel-drive Celica, Corona and Carina GT-Ts from 1982.

Early Toyota Engine Suffixes The R and T-series Toyota engines can be identified by some important suffixes. Those engines with a G suffix identify the use of a wide-angle DOHC head for high performance, E identifies electronic fuel injection, R identifies air injection and U identifies Japanese low emission standards. These suffixes also apply to other early Toyota engines – make sure you’re aware of them when shopping because output can vary by around ten percent!