| Toyota R engine | |
| Production: | 1953–1997 |
| Manufacturer: | Toyota |
| Configuration: | Inline-four |
| Block: | Cast Iron |
| Head: | Cast Iron Aluminium |
| Valvetrain: | OHV 2 valves per cyl SOHC 2 valves per cyl DOHC 2 valves per cyl |
| Timing: | Timing Chain |
| Compression: | 7.5:1-10.0:1 |
| Turbocharger: | Hitachi CT20 on 22R-TE only |
| Fuelsystem: | Carburetor Multi-port fuel injection |
| Fueltype: | Gasoline |
| Oilsystem: | Wet sump |
| Coolingsystem: | Water-cooled |
| Power: | 45- |
| Torque: | 108- |
The Toyota R family was a series of inline-four gasoline automobile engines. Designed for longitudinal placement in such vehicles as the Celica and Hilux and in production from 1953 through 1997, usage faded out as many of Toyota's mainstream models moved to front-wheel drive. Overhead cam (OHC) versions featured a chain-driven camshaft.
The 1453cc R family was produced from 1953 through 1964, and was originally manufactured at the Toyota Honsha plant.
Bore and stroke was NaN2NaN2.[1] In common with new engines of the time, it was made from cast iron (both the block and the head), water cooled, used a three bearing crank, 12V electrics and a side-mounted gear-driven camshaft controlling overhead valves via pushrods in a non-cross flow head (exhaust and inlet manifolds being on the same side of the engine).[1] Induction was by a twin throat down-draft carburettor, the compression ratio was 8.0:1 and the total weight was 155kg (342lb).[1] An LPG version, the R-LPG, was produced for the last two years.
The R engine was the Toyota engine used in the 1958 Toyota Crown, the first model to be exported to the United States. Road & Track was unimpressed with the engine on its introduction, noting that it idled quietly but was "not capable of very high revolutions per minute."
| Code | Power | Torque | Years | Comments | |
|---|---|---|---|---|---|
| R | 450NaN0 at 4,400 rpm | 1080NaN0 at 2,600 rpm | 1953–1964 | ||
| R-LPG | 1962–1964 | LPG |
Applications:
The 1490cc 2R family was produced from 1964 through 1971. It is a square engine, with bore and stroke of 78mm.
Again, an LPG version, the 2R-LPG, was produced alongside the gasoline version. Production had been gradually transferred from the original Honsha plant to the new Toyota Kamigo plant in 1968.
| Code | Power | Torque | Years | Comments | |
|---|---|---|---|---|---|
| 2R | 550NaN0 at 5,000 rpm | 1160NaN0 at 2,600 rpm | 1964–1969 | ||
| 2R-LPG | 1964–1969 | LPG |
Applications:
The 1897cc 3R family was produced from 1959 through 1968.
When introduced it had a 7.7:1 compression ratio. 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. The 3R-C was introduced to comply with California emissions laws. The 3R-LPG variant was produced for the last five years.
| Code | Power | Torque | Years | Comments | |
|---|---|---|---|---|---|
| 3R | 590NaN0 at 4,600 rpm | 1420NaN0 at 2,600 rpm | 1959–1960 | 7.7 CR | |
| 3R | 660NaN0 at 5,000 rpm | 1420NaN0 at 3,400 rpm | 1960–1968 | 8.0 CR | |
| 3R-B | 590NaN0 at 4,600 rpm | 1420NaN0 at 2,600 rpm | 1960–1968 | 7.7 CR | |
| 3R-C | emissions control – California | ||||
| 3R-LPG | 1963–1968 | LPG |
Applications:
The 1587cc 4R family was produced from 1965 through 1968.
Bore and stroke was NaNmm.
Applications:
The 1994cc 5R family was produced from 1968 through 1986. An LPG version, the 5R-LPG, was produced from 1968 through 1983.
It is a 2-valve OHV engine. Cylinder bore and stroke are NaN2NaN2. Output was 106hp at 5200 rpm and 125lbft at 3000 rpm. Trucks such as the Dyna received a version tuned for torque, with a maximum power of 80PS at 4600 rpm and torque of 1450NaN0 at 3000 rpm.
Applications:
third through sixth generation (RS50, RS60/66, RS80/RS100, and RS110). Only with LPG for taxi use in the last two generations.
The 1707cc 6R was produced from 1969 through 1974. Output is 1070NaN0 at 5,300 rpm. The 6R-B was produced those same years, while the natural gas powered 6R-LPG was produced from 1970 through 1973.
The 1591cc 7R was produced from 1968 through 1971 with a twin throat down-draft carburettor.[2]
The 7R-B was produced from 1968 through 1969 with dual SU carburetors and higher compression.
The 7R-LPG was produced from 1969 through 1970.
The 7R was similar in displacement and technology to the 4R except the wider 86mm bore and shorter 68.5mm stroke of the 7R gave different power characteristics.
| Code | Power | Torque | Compression | Years | Comments | |
|---|---|---|---|---|---|---|
| 7R | 630NaN0 at 5,500 rpm | 1230NaN0 at 3,800 rpm | 8.5 | 1968–1971 | ||
| 7R-B | 750NaN0 at 6,200 rpm | 1330NaN0 at 4,200 rpm | 9.5 | 1968–1969 | Dual SU carburettors | |
| 7R-LPG | 1969–1971 | LPG |
Applications:
The 1858cc 8R The engine was produced from 1968 through 1973.
Cylinder bore and stroke was NaNmm with a five bearing crank.
It 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 for the R family. With a 2-valve SOHC head, it impressed contemporary reviewers – Road & Track praised its quietness and free-revving nature.
The 8R engine has a closed chamber head vs the open chamber of the 18R-C. The 8R-B has dual side draft SU-type Aisan carburettors with the float bowl under the body and vacuum activated power valves with strangle plates for chokes and liquid cooled intake with a balance tube.
Toyota upped the ante again with the DOHC (but still 2-valve) 8R-G, produced from 1969 through 1972. From 1969 to Feb 1971 it was known as the 10R, but along with a removal of the tensioner gear in the interest of quieter operation, it was renamed the 8R-G to reflect the decision that twin-cam engines were henceforth to be identified by a "-G" suffix. 4,931 twin cam engines were built, all installed in the Toyota Corona Mark II (RT72) 1900 GSS. The 10R/8R-G weighed in at 170kg (380lb) and as such was both lighter and more compact than its less powerful predecessor the 9R[3]
| Code | Power | Torque | Compression | Years | Comments | |
|---|---|---|---|---|---|---|
| 8R | 810NaN0 at 5,500 rpm | 1530NaN0 at 3,800 rpm | 9.0 | 1968–1972 | ||
| 8R-B | 820NaN0 at 6,000 rpm | 1520NaN0 at 4,000 rpm | 10.0 | 1969–1971 | Dual SU carburetors | |
| 8R-D | ||||||
| 8R-E | EFI | |||||
| 8R-C | 810NaN0 at 5,500 rpm | 1740NaN0 at 3,600 rpm | 9.0 | Californian emissions controls | ||
| 8R-G | 1040NaN0 at 6,400 rpm | 1660NaN0 at 5,200 rpm | 1969–1972 | DOHC, dual side-draft carburettors |
Applications:
The 1587cc 9R was produced from 1967 through 1968. Bore and stroke NaNmm.
It was essentially a 4R with a DOHC head designed by Yamaha. The cam lobes activated the valves directly via a bucket over shim arrangement. This same arrangement was used on the 2M, 8R-G, 10R, 18R-G, 2T-G, 4A-GE and 3T-GTE engines (all designed by Yamaha).
Output was 820NaN0 at 6,200 rpm and 1360NaN0 at 5,000 rpm. It was a 2-valve DOHC design with two Solex carburettors and weighed 174kg (384lb). A total of 2,229 9R engines were built.[3]
Applications:
The twin cam 1858cc 10R was produced from 1967 through Feb 1971, when it was renamed the 8R-G. The later 8R-G version did not receive a timing chain tensioner in an effort to make it more silent.
Output was 1040NaN0 at 6,400 rpm and 1660NaN0 at 5,200 rpm.
Applications:
The 1587cc 12R was produced from 1969 through 1988. It was also built in the Philippines as the 12R-M, by Toyota's local affiliate Delta Motors Corporation.
Technical Specs (Finnish Owner's Manual from 1973 Corona Mark 1)
– Four cylinder, 4-stroke, OHV
– Bore × stroke: NaNmm
– Compression ratio: 8.5:1
– Maximum power: 900NaN0 at 5400 rpm SAE
The 12R-LPG, was produced from 1969 through 1983.
Technical Specs: 1975 590NaN0 redline 4,400 rpm
Applications:
The OHC 1808cc 16R was produced from 1974 through 1980. Power output as mounted in a 1980 Mark II was 1050NaN0 at 5,600 rpm, while a twin carburetted version produced 1100NaN0 at 6,000 rpm. The 16R-B was produced for the first two years. There was also a 16R-J version for various commercial vehicle applications.
Applications:
The 18R series shared a 1968cc block; cylinder bore and stroke was NaNmm.
The 2-valve, SOHC versions were as follows:
| Code | Power | Torque | Years | Comments | |
|---|---|---|---|---|---|
| 18R[4] | 780NaN0 650NaN0 at 5000 rpm | 142- 1450NaN0 at 3600 rpm | 1971–1981 ? | non-emissions Hilux | |
| 18R-C | 720NaN0 at 5500 rpm | NaN0NaN0 at 3600 rpm | 1971–1981 | emissions control – worldwide (Californian Standards) | |
| 18R-U | 750NaN0 at 5500 rpm | 1520NaN0 at 3600 rpm | 1975–1978 | emissions control – Japan | |
| 18R-E | NaN0NaN0[5] at 5600 rpm | 1720NaN0 at 4400 rpm | 1974–1975 | EFI, Japan only |
Applications:
The 2-valve DOHC 18R-G and its variations were produced from 1973 to 1982, replacing the 8R-G and providing a performance engine which took advantage of the entire 2-litre limit of Japan's "small car" class. 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 the head and related timing components, most parts were shared or interchangeable with the SOHC 18R. Combustion chambers were hemispheric.
In 1975, air injection was added to the Japan-market 18R-GR for improved emissions. This used Solex carburettors. A fuel injected and catalyzed Japan-market version, the 18R-GEU, was produced from 1978 through 1982. There was also a catalyzed carburetted version, the 18R-GU.
Competition versions of the 18R-G and -GE include those used in rally Celicas of the period, one of which finished second in the 1977 RAC Rally. These had 4-valve heads and were called 152E, they were of NaNmm bore and stroke and 1995or (depending on the source).[6] The Group 4 rally version of the 152E had two twin-choke carburettors, and developed 2400NaN0 at 9000 rpm.[7] Higher tuned engines developed as much as 3000NaN0 at 9,200 rpm. German racing team Schnitzer also developed a turbocharged silhouette racing version of the Celica,[6] to take on the Porsche 935. With a KKK turbocharger, the Group 5 Celica developed 5600NaN0 but reliability was less than satisfactory.[8]
| Code | Power | Torque | Years | Weight | Comments | |
|---|---|---|---|---|---|---|
| 18R-G | 1450NaN0 at 6400 rpm | 180NaN0 at 5200 rpm | 1972–1981 | 1700NaN0 | ||
| 18R-GR | 1400NaN0 at 6400 rpm | 17.20NaN0 at 4800 rpm | 1973–1975 | low compression for regular fuel | ||
| 18R-GU | 1300NaN0 at 5800 rpm | 16.50NaN0 at 4800 rpm | 1975–1978 | 1820NaN0 | emissions control – Japan. | |
| 18R-GEU[9] | 1350NaN0 at 5800 rpm | 17.50NaN0 at 4800 rpm | 1978–1982 | 1660NaN0 | EFI, emissions control (Japan). |
Applications:
The 2-valve SOHC 1968cc 19R was produced from 1974 through 1977. Cylinder bore and stroke was NaNmm. Its dimensions are the same as of the 18R, but it featured TTC-V, Toyota's licensed version of Honda's CVCC stratified charge combustion system. Output is 800NaN0. The 19R was a short-lived experiment by Toyota, and was only offered in Japanese market cars.
Applications:
The 2-valve SOHC 2190cc 20R was produced from 1975 through 1980. Cylinder bore and stroke was NaNmm. Aluminum alloy heads were used.
Initial output was 720NaN0 at 4800 rpm (900NaN0 in California) and 1620NaN0 at 2,800 rpm. Power was down slightly from 1978 through 1979 at 710NaN0 at 4800 rpm and 1650NaN0 at 2400 rpm. The final version, from 1979 through 1980, was down again at 670NaN0 at 4800 rpm (still at 950NaN0 in Canada) and 1650NaN0 at 2400 rpm.
The 20R and subsequent models featured important design changes relative to the earlier SOHC R-series engines. The head was changed from a reverse-flow to a cross-flow type with hemispherical combustion chambers and shorter valve rockers. The timing chain was strengthened. The lower block bearings were strengthened against wear, safeguarding oil pressure, and the stroke was lengthened. The changes increased torque substantially and shifted peak power and torque towards the lower speed range. The later R series engines did much to establish Toyota's reputation for reliability, which had previously been indifferent at best.
Applications:
The 2-valve SOHC 1972cc 21R was produced from 1978 through 1987. Cylinder bore and stroke are NaN2NaN2.
Output for export markets, largely unconstrained by emissions, was DIN at 5,000 rpm and 1540NaN0 at 4,000 rpm. Air injection and federally compliant emissions equipment for the 21R-C (1982–1985) dropped power down to SAE net at 5,000 rpm. The air-injected Japanese version, the 21R-U, produces JIS at 5,200 rpm and 1620NaN0 at 3,600 rpm but dropped to at 5,400 rpm and 1540NaN0 at 4,000 rpm in 1986.
Applications:
The 2-valve SOHC 2366cc 22R was produced from 1981 through 1997.
Cylinder bore and stroke was NaN2NaN2.
Initial output was 720NaN0 at 4,800 rpm and 1740NaN0 at 2,800 rpm. By 1990 the 22R was producing 810NaN0 at 5,000 rpm and 1870NaN0 at 3,400 rpm.
The first fuel injected 22R-E engines appeared in August 1982. Output of these engines is commonly rated at 780NaN0 at 4,800 rpm and 1850NaN0 at 2,800 rpm.
In 1985, the engine was significantly reworked, output was up to 840NaN0 at 4,800 rpm and 1900NaN0 at 3,600 rpm. Many parts from the newer 22R/R-E are not compatible with those from the older pre-1985 engine. Non-compatible parts include the cylinder head, block, pistons and many of the associated parts such as the timing chain and cover, and water and oil pumps (although the oil pump internals are the same).These changes also affected the 22R, therefore one can consider the 85–95 22R-E as a fuel injected version of the 85–90 22R with only minor differences, if any.
Toyota swapped the dual-row timing chain used in older engines for a single-row chain with plastic guides in 1983. The new system reduced drag on the engine but introduced a new maintenance problem. After about 100000miles of operation, the chain may stretch to the point that the hydraulic-operated chain tensioner cannot take up any more slack. The timing chain then impacts the plastic driver's side chain guide, breaking it within a short period of time and creating a noticeable chattering sound in the front of the engine, especially when cold. If the engine continues to be operated without the guide restraint, the chain will vibrate excessively on the driver's side and stretch rapidly. The result is any of several failure modes.
First, the loose chain will reduce ignition timing accuracy, which usually results in noticeably rough running. Second, it may jump a tooth on the drive sprocket or break entirely, which almost always results in major damage to an interference engine. Third, the stretched chain can slap against the side of the timing cover and wear through the metal into the coolant passage behind the water pump, resulting in major damage to both the oil and cooling systems (sometimes mis-diagnosed as a head gasket failure). The damaged aluminum timing cover is difficult to repair effectively and is typically replaced after such an event. Aftermarket timing-chain kits for the 22R/R-E typically include steel-backed guides that do not readily break even after the initial chain stretching has occurred, permitting the chain to run beyond the 100000miles point without further incident. However, some Toyota mechanics will recommend the plastic guides as they will break when the timing chain is stretched; When the guides break a noticeable chatter is heard from the timing chain slapping on the cover, warning the operator of a worn timing chain.
The turbocharged 22R-TE (sold from late 1985 through 1988) produced 101kW at 4,800 rpm and 2340NaN0 at 2,800 rpm.
These engines are extremely well known for their durability, decent fuel efficiency and good low to mid range torque.
However, its weakness is high-end power. The 22R has a large displacement and a strong block, but its comparatively long stroke and restrictive head limit its use in high revving applications. Thus, the Toyota 18R-G, 2T-G, 4A-GE and 3S-GE 4-cylinder engines are better suited for performance applications.
A popular modification to the early 22R is to use a 20R head. Contrary to popular lore, the 20R head does not have smaller combustion chambers. The misunderstanding originated when the 22R came out and an advantage was its higher compression ratio, so swapping a 20R block with a 22R, there was a compression increase. The 20R head has straight ports, so can flow better than the 22R head, improving high RPM power. The 20R head is a simple bolt-on modification for the pre-1985 block, but also requires the use of the 20R intake manifold, making it almost impossible (there's a lot of matching necessary) to use with the 22R-E EFI system.[13] For blocks 1985 and onwards, further modifications are required.[14]
| Code | Power | Torque | Years | Comments | |
|---|---|---|---|---|---|
| 22R | 720NaN0 at 4,800 rpm | 1740NaN0 at 2,800 rpm | 1981–1990 | carb, dual row timing chain ('81–'82)carb, single row timing chain ('83–'90) | |
| 22R | 810NaN0 at 5,000 rpm | 1870NaN0 at 3,400 rpm | 1990–1995 | ||
| 22R-E | 780NaN0 at 4,800 rpm | 1850NaN0 at 2,800 rpm | 1983–1984 | EFI, single row timing chain | |
| 22R-E | 840NaN0 at 4,800 rpm | 1900NaN0 at 3,600 rpm | 1985–1997 | EFI, single row timing chain | |
| 22R-TE | 1010NaN0 at 4,800 rpm | 2340NaN0 at 2,800 rpm | 1986–1988 | turbocharged, single row timing chain |
Applications:
