The 7A-FE is a direct physical swap into the AE-92 Corolla; needing no special (modified) mounts or axle shafts. This is probably the easiest and cheapest power upgrade that maintains good reliability with ready availability of replacement parts.
The 7A-FE has the same 115hp as the big port 4A-GE, but produces 115lb/ft of torque at 2800 RPM, whereas the 4A-GE produces about 100lb/ft at about 4800 RPM. It is not a great hp gain over the 4A-FE, but the fat torque curve, starting at such a low RPM will make you smile.
4A-FE: 1988 - 1992. 102hp @ 5800, 101lb/ft @ 4800
4A-GE: 1986 - 1989. 112-115hp @ 6600, 97-100 lb/ft @ 4800 [Big Port]
4A-GE: 1991 - 1992. 130hp @ 6800, 102 lb/ft @ 5800 [Small Port]
7A-FE: 1993 - 1998. 115hp @ 5600, 115 lb/ft @ 2800
For this swap I recommend you get an engine and gearbox to get the full benefit of the engine’s torque potential.
The 4A-FE gearbox will work, but the 7A gearbox has a taller first gear, meaning you can go further before you need to shift to second, and there is no sacrifice in accelleration.
DO NOT use the 4A-GE gearbox; you will be sorry. The 4A-GE gearbox has a higher final drive ratio, 4.3:1, and you will run out of revs real quick. (FE gearboxes have a 3.7:1)
At 70 mph in 5th gear, the engine is turning approximately 500 RPM less with the FE gearbox, than with the GE gearbox.
The 7A-FE can be run on the 4A-FE wiring and ECU, but you will need to change out the distributor. I think the 4A-FE distributor will work, but am not sure. Maybe a distributor from an older Celica ST (7A-FE) will work. Again, I am not sure.
Using the 4A-FE ECU and wiring, you will loose the protection of the knock sensor, and the 4A-FE has a higher rev limited speed, so you could inadvertently over rev the 7A-FE engine if you are not careful.
You should get the complete engine wire harness, ECU, relay box and all the sensors from the engine compartment of the donor car. Don’t forget the oxygen sensors and wires. My 7A-FE engine uses two; the second one goes behind the catalitic converter, and requires a “bung“ installed in the exhaust pipe. The AE-92 bodies all seem to have a hole in the passenger side of the hump/tunnel in line with the shifter (with a rubber plug in it), through which the wire needs to be run for the second O2 sensor.
The most difficult part of this swap, as in most swaps, is the wiring.
There are several ways to go about the wiring, and I have done it the hard way twice; by finding the individual wires at the connectors and matching two wire diagrams to get the connections I needed. Not recommended.
Wiring the hard way
The easiest way to get your wiring done, is to pay someone who is proficient at this task; send them both engine harnesses, and get back a plug and play harness that will connect your new engine to your car.
There are a few guys on here (TN) that will do this for you, but I can’t think of the names right now. Search around, get some recommendations.
Tweak’d Performance in South Carolina (used to be Pheonix Tuning) are specialists at this. I had them do the 4A-GZE harness to go into my FX-16. The harness I got with the engine had more than 50% of the wiring, several connectors and some necessary components missing. It cost an arm and a leg to build a proper harness (because of the missing stuff), but to me it was absolutely worth it. Plugged right in, fired right up. I only had to make two wire connections.
In this photo the (already modified) wiring from my wrecked GT-S is being swapped into the SR-5 which replaces it.
If you do the wiring yourself, the recommended method is, before installing the engine, strip the wrapping from the wire harness for the “going in” engine. Connect it to all points on the engine, ECU and sensors necessary for engine operation. Zip tie the various bends and “T “and “Y” sections to maintain the form of the harness. Strip the “coming out” engine wire harness and lay it parallel to the “going in” engine harness.
Identify the matching wires between the two harnesses one at a time. Swap out the connectors at the car end of the “IN” engine harness with those of the “OUT” engine harness, by either pulling the pins from the connectors, or cutting and soldering the necessary wires. Do one-at-a-time.
I recommend you have the Toyota Shop Manual to show you how to remove the pins from the connectors, as they aren’t all the same.
Some wires on the “IN” harness, might not have a match on the “OUT” harness (e.g.. second oxygen sensor on the 7A-FE) so those wires you will have to use as is, or make fit.
After getting all your connections done, zip tie the harness to make it neat (do not wrap it yet), install the engine and harness and get it started. This way, if you have any problems, you won’t need to undo the nice wrapping job you just did, to find your error.
If the engine starts and runs correctly, remove the wiring, wrap it neatly, and reinstall.
Use the 4A-FE engine mounts.
On the carbureted cars, you should swap the relay box.
The relay boxes look the same, but the box for the SR-5 (carbureted) is missing one 7.5amp fuse and socket connectors that is in the 7A-FE box.
I haven’t checked the wiring diagram, but I think it must be for the FI fuel pump. All the connectors underneath are the same between both wire harnesses.
On the FI cars swapping the boxes should not be necessary.
Swapping into a carbureted car, you will need to swap the fuel tank, main and return fuel lines for "FI" items. You could probably get away with just puting in an in-line electric pump, but you will not have a baffel in the tank to stop the fuel from leaving the pick-up pipe high and dry when making a corner with less than 1/4 tank of fuel. This can cause your lower sphincter muscle to contract if it happens while you are making a left turn in front of a semi, and your engine sputters.
The carburetor float bowl compensates for that so the carbuteted cars don't need baffels.
This photo shows the FI fuel filter and charcoal canister mount bracket. Need to swap that.
This is the charcoal canister bracket for the carbureted car. No mount for fuel filter.
I don't have any photos of the actual installation, because it is a straight forward process, just as if you were replacing a 4A-FE with another 4A-FE.
If anything else comes to mind, I will add later.
If anybody thinks of anything I left out, please add the info.
Added 1/7/2012: Get the pigtails from the dash harness to the ECU, and dash harness to engine harness also.
People have done this many times before, but finding a lot of detailed info isn't so easy to come by. But I don't know anyone with an AE95 who has tried to use a Honda ECU...
please help me
Linear Mode
