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Niku-Sama

EJ22 swap with existing 4EAT

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ok so i have an odd ball and i am contemplating getting an engine that i can rebuld and replace the old engine when i need too only thing is...

 

the car i have now has an existing 4EAT engine

its a 1990 Turbo Loyale w/ Full time 4WD and a 4EAT transmission, all stock except the aftermarket cruise....which i am not sure how its working but it does.

 

any way i havent really seen any thing on this, i assume most of it would be the same but seeing how the 4EAT is also in the other (newer) cars would i need an adaptor plate and would i really need a shorter shaft?

 

also what about wiring for the transmission, this is an electronicly controlled 4 spd auto trans right? is the system for it stand alone from the rest of the computer system or is it tied into it? (i imagine its tied in)

 

none of the manuals i have really tie into the 4EAT wiring on the '90 loyale, not sure if it made it into other loyales either.

 

i almost wonder if its a direct swap for a 1990 legacy motor

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The 4EAT has its own computer. So it should be no hassle with wiring.

What you might encounter is a problem with the torque converter.

I dont know if the Loyale TC will mate up with the EJ and/or the other way around.

The way to find out is to have a 4EAT flexplate and see if it mates up to the EJ output.

If that doesnt work, try fitting a EJ TC to the 4EAT input.

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well, the bellhousing on the engine side is the same. so yea, you'll need an adapter plate.

 

I would be you'd need the EA torque converter to make sure the starter gears engage.

 

you might be able to find an EJ flex plate to mount to the EA torque converter, or just modify the EA one like we do with the flywheels.

 

 

the wiring will be the interesting part. as there are a number of wires going from the ECU to the TCU. But it is theoretically possible, as I know people have used the EJ TCU with an EA engine/trans.

 

 

 

also, yea, a loyale with a 4EAT is pretty rare. only in '90, and only the turbos. almost all of them have the 3AT.

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Like chux said the wiring will be interesting as the TCU does use input from the motor, I think just the TPS but maybe more complicated than that too. It's mostly a stand alone affair, but it is integrated slightly, nothing scary complicated though.

 

If the EJ and EA TPS signals differ I'm not sure what that would mean.

 

Might it be possible to score an EJ 4EAT, like an entire car? Then you'd avoid the adapter plate issue, the TCU issue, and might get better gearing too.

 

If you were really ambitious you could swap an EJ front diff or case onto the 4EAT trans body and make it a bolt on affair. then you can get one of those front locking differentials to boot.

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I'm in the middle of the same thing. Easiest way is to get a blown EJ 4EAT, and put it's front housing on your trans. Just make sure it isn't the pump that's blown. Second option is to use an adapter plate like the manuals. Everything is dimensionally the same, all the same differences since there isn't a specific engine for auto vs manual, they're all the same.

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i have a bad EJ 4EAT if you're interested in the front housing, but it's probably not worth it unless you're really close to me.

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hmm i'll just keep an eye out for a donor car, i'm not ina huge hurry it runs pretty good now aside from the pre turbo exhaust leak.

 

so i guess a car with a 4eat and the bellhousing sounds like the best way to go.

 

i dont know how accurate it is but the TPS thing, in the manual i have it says its more of a switch than a sensor, knows when its closed and wide open but this haynes manual doesent document 4eat real well

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i think it's similar in the 4EAT - there is a switch function of the TPS. somehow the 4EAT needs to "know" when to shift though, I'd think it's getting some kind of input from the ECU/engine sensors.

 

EA/ER ECU's are interchangeable between manual and automatic transmissions, so it's not overly complicated whatever role they play.

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The tach signal is different. I'm not sure if the EA 4EAT TCU is sensitive enough to use the logic-level tach from the EJ ECU. My educated guess is that it will work; if not you'll need a couple diodes and attach them to the coil pack, no big deal. Without the signal the tranny won't know when to shift.

 

The TPS and other stuff should match up fine.

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i think it's similar in the 4EAT - there is a switch function of the TPS. somehow the 4EAT needs to "know" when to shift though, I'd think it's getting some kind of input from the ECU/engine sensors.

 

EA/ER ECU's are interchangeable between manual and automatic transmissions, so it's not overly complicated whatever role they play.

 

hmm that gets me thinkin, though could be a real pain in the rump roast if i have to figure out where to tie it into, but it could go the complete oppisite way and have the TCU be plug and play with the rest of the harness. hmm

 

i wonder if it would be more beneficial to go with something close to my cars age (its a 1990) and mabe i'll get lucky and it'll have the same setup with an EJ in it.

 

i cant imagine that a earlier EJ 4eat car is going to have much different input from EA 4eat.

 

mabe i should go into the junk yard and see if the TCU part numbers are the same and the connectors for the harness are the same

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mabe i should go into the junk yard and see if the TCU part numbers are the same and the connectors for the harness are the same

 

Just swap the Bellhousing/Diffholer front section of the tranny with an EJ one. Install you're existing diff in the EJ housing. Good time to install new ends seals and even bearing if needed. Use EJ Torque converter and Flexplate, or redrill you're flexplate to fit on the EJ motor if you want to keep you're TC.

 

Alternately, you could get a whole EJ tranny, and just splice the harness connectors off you're tranny, the wirng is all 100% the same up to 97ish. However, you will need the matching 3.9,4.11,or 4.44:grin: rear diff to match whatever trans you get.

 

 

Tach signal will be fine, as long as you hook up the EJ harness to the tach on the dash, the trans will get the signal too cause the split in the wiring is in the dash. The only thing that will be *off* somewhat is the TPS signal, which is in a different Ohm range on EJs. However, since the TCU monitors the voltage on the circuit(0-5v), not the resitance directly, I have a hunch that it will work out all the same.

Edited by Gloyale

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Hey, I know this is an old thread, but I am in the same boat. I have a 1990 loyale turbo w/4EAT and I am thinking about doing the EJ swap as well, and I would like to keep my transmission. How did this turn out, or did it??

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also, yea, a loyale with a 4EAT is pretty rare. only in '90, and only the turbos. almost all of them have the 3AT.

 

88 and 89 GLs the 4EAT was an option on turbo cars as well.

 

Swap will work fine.

 

TCU will be a little goofed up by the missing TPS, but otherwise will run fine.

Edited by Gloyale

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88 and 89 GLs the 4EAT was na option as well.

 

Swap will work fine.

 

TCU will be a little goofed up by the missing TPS, but otherwise will run fine.

 

Thanks (again), good to know. I think I am one of the few that actually like the 4EAT and will keep it after doing an EJ swap. For my DD needs, the auto is great! I will keep that on the back burner...

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88 and 89 GLs the 4EAT was an option on turbo cars as well.

 

yep, I should have been more specific. I was saying only the '90 would have been actually called a loyale.

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