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...
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