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The definitve guide to EFI transplants
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4AGE Rear Wheel Drive ConversionThe Toyota 4AGE engine has evolved through five different generations since its introduction in May 1983.The reason for the popularity of the 4AGE for transplants stems from an excellent design, good power output, light weight, compact size and high reliability.The aim of this page is to explain the
variations between the different generations and detail the specifications
to assist you in selecting the best one for your application.
4AGE Development1983 saw Toyota release a new generation engine called the 3A. This engine was a simple 1500 cc single overhead cam, carburettor fed, electronic ignition engine and it was fitted to the AE 70 Corolla range of rear wheel drive cars. This engine was joined in May 1983 by the 4A 1587 cc variant and the twin cam, fuel injected 4AGE 16 valve derivative. There were eventually 1300 and 1800cc SOHC versions also produced (2A and 7A), however, the twin cam was manufactured only as a 1600.Rumours abound that Lotus had been working with Toyota on developing a new small high performance 16 valve engine that both could use. Lotus was planning on putting it into a small transverse mounted mid engined sports car, but for various reasons pulled out. Toyota continued with the engine development into production, and the rest is history. Apparently the sports car concept eventually turned into the MR2. I don’t know if this story is true, but it certainly is nice to think so. The 4AGE head arrangement (valves, combustion chamber design, etc) is fairly similar to the UK Cosworth BDA series 16 valve engines used with great success by Ford in the 1970s. Bit of useless information - the TA 63/RA 63/MA 63 etc series of Celicas and Supras had Lotus input into the suspension set up which clearly shows if you have ever driven a well set up IRS model on twisty open roads. Pity the car itself is so ugly! The RWD 4AGE version is the easiest option for use in RWD cars, however, the factory engine output is 'only' 88 kW, and they are all getting pretty old now. The saving grace is that all later generations of the engine will literally bolt up to a RWD gearbox, opening up the availability of a wide range of power outputs. The downside comes from the fact that the newer generation engines are optimised for FWD layout only and require considerable modification to fit into a RWD body shell in most cases. Bolting a FWD 4AGE to a RWD gearbox and mounting the unit in a car is the easy part - the difficulty lies in getting the intake systems and radiator plumbing to fit. The 20 Valve motor poses even more problems as the distributor is driven off the back of the exhaust cam and may need a firewall recess to fit unless some radical modifications are done to the ignition system. First Generation 4AGE 83.5-87.5The first generation 4AGE was introduced in May 1983 and remained in production until May 1987. The engine is externally identified by silver cam covers with black and blue lettering, hence they are often referred to as 'blue and black tops'. This generation was produced in transverse form (AW 11 MR2 and AE 82 FWD Corolla) and RWD longitudinal from (AE 86 Corolla GT/Corolla Levin/Sprinter Trueno and AA 63 Celica). Transverse engines have the throttle body at the flywheel end of the inlet manifold while RWD have the inlet at the pulley end.This generation features Toyota Variable Intake System (TVIS) which is a set of four butterflies located in the inlet system next to the head. These butterflies are shut below approximately 4500 RPM, effectively blocking airflow to one valve per cylinder, increasing the air speed and thus improving mid range torque. They are opened by the ECU via a small plastic vacuum tank and solenoid triggered diaphragm actuator located under the inlet manifold and open above this speed. The effect is similar to a second throat opening on a carburettor. These engines develop in the vicinity of 88 kW. Depending on where in the world the engine was sold it will have either MAP sensor or Air Flow Meter. Second Generation 4AGE 87.5-89.5The second generation engines were released in May 1987 and are identified by silver cam covers with red and black writing, hence red and black top. These engines retained TVIS and remained on the market until May 1989.They are similar to the first generation engines with the same performance, however, they have larger diameter bearings, are transverse layout only and have a stronger block identified by 7 external vertical ribs as opposed to three on the earlier engines.A supercharged model, the 4AGZE, was also released. This engine has unpainted cam covers. The engine fitted to MR2s has the supercharger outlet to the intercooler facing the flywheel end of the engine block and a normal distributor. The model fitted to the FWD Trueno/Levin has the intercooler plumbing facing upwards (the intercooler mounts on top of the cam covers) and has a crank angle sensor fitted in place of the distributor. This engine is fitted with twin coil packs instead of a conventional distributor arrangement. Power output is 107 kW. All engines are AFM and transverse layout only. Fitted to face-lifted AW 11 and AE 92 Third Generation 4AGE 89.5-91.6The next generation engines were introduced in May 1989 and remained in production until June 1991. Two types exist. The 16 valve has silver cam covers with red lettering only, and so are called red tops. These engines have oil cooled pistons, an external oil drain from the head to the sump (located behind #4 inlet) and the ignition leads run underneath a cover between the cam covers. Power is increased to 100 kW and all engines are MAP sensored. This is the final 16 valve variant produced. These engines have dispensed with TVIS and feature smaller inlet ports.The 4AGZE has the same additions and utilises the twin coil distributor less ignition system. These 4AGZEs were produced FWD only. Power increased to 120 kW and the supercharger has a smaller diameter pulley compared to the earlier version. These were fitted to AE 92s only. Fourth Generation 4AGE 91.6-95.5The fourth generation, released June 1991, saw the demise of the 16 valve in naturally aspirated form and its replacement with the 20 valve. This engine has silver cam covers with chrome lettering, and is referred to as the silver top. Ignition leads are hidden underneath a central cover. Three inlet valves per cylinder are operated via a variable cam timing mechanism while exhaust valves are standard set up. The distributor is mounted off the back of the exhaust cam. The engine is fitted with 4 throttle bodies and is AFM sensored. This engine was sold new in Japan only and also has factory tubular headers. Power output is 120 kW but with less torque than the 4AGZE.The 4AGZE is virtually identical to the previous model but produces slightly more power. Both engines were available in the AE 101 model only. Fifth Generation 4AGE 95.5-The final generation of 4AGE is available in 20 valve variant only (as far as I have been able to establish - if anyone knows of a 4AGZE model please get in touch), and was released in May 1995. This engine is distinguished by black cam covers (surprise - 'black top'!) and MAP sensored air flow measurement, otherwise it looks similar to the previous version. Power output is 123 kW. There is no supercharged 20 valve version although a few have been built by amalgamating various parts. Again, it is only available in the AE 111 Corolla series.4AGE SpecificationsThe following tables contain the basic features that differentiate the various 4AGE models. The information is Japanese sourced from Hyper Rev AE 86/92/101/111 Levin/Trueno Magazine Volume 18 (News Publishing Co Japan).Local variants could be slightly different
due to emissions regulations etc, but the basic features are the same.
Don't forget that a 15 year old engine is not likely to develop the same
power as it did when factory fresh.
Note the higher output of the early 4AGE
RWD engines. A few words about measuring power (Thanks to Matti Kalalahti):
So yes, it is true - Japanese horses are smaller than European ones! Next: Engine Installation |
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Copyright © 2000 SpeedTECH Last modified: January 23, 2000 |
