The 4A-GE Guide
We examine the range of Toyota 4A-GE engines.
When the Toyota 4A-GE debuted in Japan in 1983 it quickly established itself as one of the best high-tech four-cylinders in production. Riding its wave of success, the 4A-GE then morphed into supercharged, 20-valve and a host of other versions. Their combination of light weight, compactness, reliability and potential power output make them highly sought after for conversions, kit cars and off-road racing buggies.
So let’s take a look at the progression of the 4-AGE and the different versions you’ll find at the import wreckers...
First Generation 4A-GE
The first incarnation of the 4A-GE was seen from 1983 to 1987 under the bonnet of the Japanese market AE82 Corolla, AW11 MR2, AE86 Corolla GT, Corolla Levin, Sprinter Trueno and AA63 Celica. These first generation 4A-GEs can be identified by their silver valve covers with black and blue lettering.
The Toyota 4A-GE was one of the first mass-produced engines to combine a DOHC, multi-valve cylinder head with electronic multi-point fuel injection. The cylinder head is designed to provide a 50 degree valve separation (compared to 22.3 degrees in low output 4A-FE derivatives) and employs belt driven camshafts.
The 4A-GE also brought Toyota Variable Intake System (TVIS). This system comprises a set of butterflies which are used to block the flow of induction air through one of the intake valves during low to mid rpm operation. This is claimed to improve torque. At high revs, the butterfly valves open to allow both intake valves breathe efficiently.
Bore and stroke dimensions are 81 and 77mm respectively and the compression ratio was initially set at 9.4:1. The engine management employs a MAP load input, a distributor and multi-point EFI. Power output of the first generation 4A-GE is 96kW at 6600 rpm and 149Nm at 5200 rpm – very respectable in the early ‘80s.
Most 4A-GEs were tied to a 5-speed manual gearbox but an optional auto transmission was available in almost all models. The engine is transversely mounted in the AE82 Corolla and AW11 MR2 while it’s longitudinally mounted in the AE86 Corolla GT, Corolla Levin, Sprinter Trueno and AA63 Celica.
This is probably one of the least desirable 4A-GEs - but it remains popular because it’s the only generation that comes in a longitudinally mounted, rear-wheel-drive configuration.
Second Generation 4A-GE
From 1987 to 1989 the second generation 4A-GE was produced.
The second generation is very similar to the first except the block is strengthened, the gudgeon pin and big-end bearing diameter are increased and we believe the crankshaft is strengthened. These upgrades make it a much better base for high performance tuning.
The existing MAP load sensing system was exchanged for an airflow meter and, interestingly, power and torque were slightly reduced. The second generation 4A-GE slipped to 88kW at 6600 rpm and 142Nm at 5200 rpm (a drop of 8kW and 7Nm).
Visually, there’s not much to identify a second generation over the first except for a silver valve cover with red and black lettering. Note that all second generation engines are transversely mounted in the AE92 Corolla, Levin/Trueno and updated AW11 MR2. Again, a choice of 5-speed manual or auto transmission was available.
Third Generation 4A-GE
Toyota employed the third generation 4A-GE between 1989 and 1991.
The third generation engine has numerous changes - the most important being the removal of TVIS and fitment of a ‘small port’ cylinder head. To improve efficiency, the compression ratio was increased to 10.3:1 – a move which necessitated the fitment of a knock sensor and the recommendation for premium unleaded fuel. Piston oil cooling jets were added and the management system again reverted to a MAP sensor arrangement.
Toyota achieved a considerable power increase with the third generation 4A-GE - 103kW at 7200 rpm and 147Nm at 6000 rpm. This makes it the most powerful naturally aspirated 4A-GE 16-valve ever produced.
The third generation 4A-GE came fitted to the AE92 Corolla GT and top-line Carina. The third gen engines are identified by their red writing valve cover writing and the concealment of the spark plug leads.
These were the last naturally aspirated 4A-GE produced with a 16 valve head.
Fourth Generation 4A-GE
The fourth generation 4A-GE – released in 1991 - saw the replacement of the faithful 16-valve head with a sophisticated 20-valve unit.
The 4A-GE 20-valve engine uses essentially the same block as earlier models but benefits from an all-new new cylinder head boasting three inlet and two exhaust valves, variable inlet cam timing and quad throttle bodies. It’s a monumental improvement on an already impressive engine.
The 4A-GE 20-valve also receives different pistons (with oil squirters), a 10.5:1 compression ratio, lightweight rods, tubular headers and an airflow meter. This highly sophisticated engine loves to rev and is capable of generating 118kW at 7400 rpm and 162Nm at 5200 rpm.
These first versions of the 20-valve engine came in the AE101 Corolla series only. The engine can be identified by its 20-valve designation and silver valve cover.
Fifth Generation 4A-GE
The final iteration of the 4A-GE was released during 1995 and continued sales until 1999.
Again available only as a 20-valve version (which is no bad thing!), the fifth generation 4A-GE is revised to include slightly larger throttle bodies with rubber intake trumpets (instead of plastic), a 11:1 compression ratio and different airbox. And, yet again, the ECU load input was switched back to a MAP sensor – it seems Toyota couldn’t make up its mind...
These alterations lifted power slightly to 123kW at 7800 rpm making this the most potent naturally aspirated engine in the series. This fifth generation 4A-GE 20-valve (identified by its black valve cover) is fitted to the front-wheel-drive AE111 Corolla series and comes with either a manual or automatic transmission.
Supercharged 4A-GZE
A supercharged and intercooled version of the 16-valve 4A-GE was sold during the second, third and fourth generation periods (between 1987 and 1995).
The blown engine (dubbed 4A-GZE) is equipped with a positive displacement roots-type supercharger which blows through an air-to-air intercooler. The SC12 supercharger (pictured here) incorporates Teflon coated rotors and an electro-magnetic clutch which is controlled by the ECU. The conrods of the supercharged engine are apparently stronger than in conventional 4AGs and the static compression ratio is lowered.
In early versions, the compression ratio is cut to 8:1 using ceramic coated forged pistons, the distributor type ignition uses knock sensor feedback and an airflow meter is used. Power output is a mild 107kW at 6400 rpm but there’s a relatively strong 186Nm at 4400 rpm. This early 4A-GZE can be found in AW11 MR2s.
The next version (released during the third generation 4A-GE) brought an increased static compression ratio of 8.9:1, direct-fire ignition with a MAP sensor and the adoption of the small port head. Still, power shot to 121kW at 6400 rpm and torque swelled to 201Nm at 4400 rpm. The second-generation 4A-GZE is fitted to AE92 Levins and Truenos.
The most powerful 4A-GE is the last incarnation of the 4A-GZE (released during the fourth generation period). We believe that a small diameter supercharger pulley gave a boost increase which attained 125kW and 206Nm – an output similar to engines displacing around 2.5 to 3 litres... This engine was available in the front-wheel-drive AE101 Corolla series.
This is the pick of all 4A-GEs but keep in mind it’s designed for transverse mounting – you’ll need to get creative if you want to mount the engine longitudinally.
Unfortunately, Toyota never fitted a turbocharger to any of the 4A-GEs or combined the 20-valve head with a supercharger. However, it’s quite possible to mix and match original Toyota parts to create the ‘ultimate’ 4A-GE...credit : www.autospeed.com
