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D/R EA82 swap into AWD Auto EA82T ??


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21 replies to this topic

#1 4RnrRick

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Posted 03 November 2006 - 06:50 AM

I just acquired myself (2) Subies. :headbang:
The good car - 01/89 GL-10 Wagon, AWD, Auto, EA82T, Bad Motor (hole in block)
The donor car - 10/89 GL Wagon, D/R, Manual, EA82 SPFI, Bad Body (tree fell on car)
So I want to swap the good motor EA82 into the GL-10. What problems can I expect? Both cars are complete.

From my research it appears that I will have to swap Motors, Downpipe, Complete engine wiring harness, ECM and maybe the engine crossmember.

The one main question I have is what about the tranny wiring? :confused: Will the engine harness from the car with the manual tranny support the Auto tranny? or is that wiring seperate? Do these cars have a TCU? (Transmission Control Unit). Or to get everything to run correctly - will I HAVE to convert the good car to a manual D/R tranny?

My goal with these cars is basically to make one good running car for my wife to drive. (note - my wife doesn't drive a stick) :-\

#2 calebz

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Posted 03 November 2006 - 10:17 AM

If the tranny (auto) in the good car is ok, just leave it there and swap motors/motor harnesses.

Or you could put the turbo stuff on the SPFI shortblock. Then you wouldn't even have to swap harnesses.

The FT4wd auto has its own TCU, so that shouldn't be a problem.

Also, when going from turbo to non turbo I don't think you have to change the crossmemeber. Only if you are swapping the other direction.

#3 4RnrRick

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Posted 03 November 2006 - 10:53 AM

If the tranny (auto) in the good car is ok, just leave it there and swap motors/motor harnesses.


Yeap, Thats what I want to do.

Or you could put the turbo stuff on the SPFI shortblock. Then you wouldn't even have to swap harnesses.


Since the good Auto car has the blown EA82T - I have to swap in a new bottom end already. So I figured I might as well just swap the complete motor into it. that way I don't have to spend time tearing the engines down.

The FT4wd auto has its own TCU, so that shouldn't be a problem.


Does it have its own harness or is it intergrated into the engine harness?

Also, when going from turbo to non turbo I don't think you have to change the crossmemeber. Only if you are swapping the other direction.

Thats good news!






So can anyones else confirm these items.......Sounds like it shouldn't be too bad of a swap!

#4 GeneralDisorder

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Posted 03 November 2006 - 11:32 AM

Since the good Auto car has the blown EA82T - I have to swap in a new bottom end already. So I figured I might as well just swap the complete motor into it. that way I don't have to spend time tearing the engines down.


Actually, you will spend MORE time trying to graft the SPFI harness into the MPFI Turbo car than it would take to just swap the bottom ends. Although the higher comp. bottom end may not be a good idea for your spouses daily driver. That's not a known reliable combo.

Looks like you must be really close to me (I'm in Willamette, near chevron and Albertsons) - I just finished an auto to manual swap, and I've done SPFI conversions too. Maybe I can help you out a bit.

GD

#5 4RnrRick

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Posted 03 November 2006 - 12:20 PM

Actually, you will spend MORE time trying to graft the SPFI harness into the MPFI Turbo car than it would take to just swap the bottom ends.


My plan was to just swap the complete engine wiring harness & ECM - not to graft them together. That will work right ???




Although the higher comp. bottom end may not be a good idea for your spouses daily driver. That's not a known reliable combo.


Thats another reason why I would rather NOT build a high compression turbo motor.




Looks like you must be really close to me (I'm in Willamette, near chevron and Albertsons)

I'm 20 miles south of Eugene.

#6 GeneralDisorder

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Posted 03 November 2006 - 01:00 PM

My plan was to just swap the complete engine wiring harness & ECM - not to graft them together. That will work right ?


Well, to put it bluntly, no.

See the problem is that while the engine ECU and the tranny ECU are indeed seperable, they are not seperate harnesses per-se. The tranny ECU relies on some of the engine sensors (IIRC), and the harnesses are all tied in together, wrapped in plastic, taped, tied, and mangled. It's a bit like siamese twins.... could you seperate them? Yes probably. Is it always the wisest plan of action? NO. They share all kinds of grounds and test connectors all through the harness. Just for an example, I spent about 5 hours seperating the SPFI engine control system from a 90 Loyale harness so I could graft it to my Brat.... and that was AFTER I got the thing out of the car, which took an hour at least, and to do it you have to remove the drivers side fender.

If you want to go this route, it's best to swap the entire vehicle harnesses wholesale - but that means her learning to drive a stick.... It also means you have to swap the pedal assembly, tranny cross-member, rear driveline, rear diff, dash wireing harness, guage cluster, etc, etc. I'm not even sure *I* know what all would need to be swapped for that to happen. The auto to manual swap I just completed took about 3 weeks of non-full-time work and both cars were already SPFI. I did a complete reseal on the engine and moved engine+tranny from one car to another. But both were Loyales, and both were very similar.

Thats another reason why I would rather NOT build a high compression turbo motor.


I feel ya brother - I wouldn't drive one myself, let alone give it to a spouse that's clueless about automobiles (in my case).

I'm 20 miles south of Eugene.


Whoa! I mis-judged the size of the valley I guess. I saw Willamette and didn't really think about it. I'm in West Linn, just south of Portland. Still - I could drop down there for some beers some afternoon if you need some skilled advice.

GD

#7 4RnrRick

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Posted 03 November 2006 - 01:27 PM

Well, to put it bluntly, no.

See the problem is that while the engine ECU and the tranny ECU are indeed seperable, they are not seperate harnesses per-se. The tranny ECU relies on some of the engine sensors (IIRC), and the harnesses are all tied in together, wrapped in plastic, taped, tied, and mangled. It's a bit like siamese twins....


I looked in my haynes manual for an Auto Wiring harness for the '89, but I couldn't find anything. Guess I will need to dig out my FSM on CD to see how bad it is.

Does anyone have a wiring schematic for the FT Awd Automatic Tranny?

Or is there already a thread talking about this???

BTW - I'm a Toyota nut and I'm very capable in the garage. I've swapped a '89 Supra/Cressida 7MGE [3.0L I-6] into my '85 Toyota 4Runner (oringally a 22RE [2.4L I-4]) and I've swapped a '00 Tacoma 3rz [2.7L I-4] in my 2wd '85 22rte [2.4L Turbo I-4] which is now a 4wd. So doing a little wiring isn't that big of a deal - but I do want to find the easiest and quickest route to do the job.

#8 GeneralDisorder

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Posted 03 November 2006 - 01:45 PM

I don't think it's all *that* bad, but making the harnesses play nice with each other might suck. Things like the 3 pin vs. 4 pin TPS..... the 4EAT (your AWD slush box) only came with the EA82T, and the legacys (EJ22), so I'm not sure if the TCU will play play friendly with the "plain jane" 3 pin TPS used with the SPFI..... and there's lots more strange things with the 4EAT I understand. It's basically a Legacy transmission with an EA bell-housing and it only came out with the EA82T's and only in the later 80's. But sadly I don't have an FSM that covers the 4EAT so I'm mostly blind on that one...... the fact that it was never coupled to a throttle body engine (and thus I'm assuming never intended to be) might make the TCU very unhappy, and because of it's programming might actually make it impossible for the TCU to run properly. Only careful study of the FSM would answer that question.... and maybe not even then.

You should ask over in the new-gen forum. The Leganus nuts over there that deal with the 4EAT all the time might know more.

Always seems easy before you start doing it. hehehe. Although I'm sure those yota's were just as painful in the wireing department.

GD

#9 4RnrRick

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Posted 03 November 2006 - 04:20 PM

Well I looked at my FSM on CD and the wiring diagrams SUCK (low res). Guess I will have to figured it out the hard way when I tear into it and start comparing wires.

Worst case, I guess I will just swap the D/R Manual tranny (and pedal assembly, driveline, CV shafts, etc..) over into the Auto car and just sell it for some cash. I hope it doesn't come to that because thats alot more work.

UNLESS anyone else can offer up some usual info to say otherwise?

#10 NorthWet

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Posted 03 November 2006 - 08:07 PM

Two alternate suggestions:

1) Put another turbo motor in it. Bottom ends are pretty sturdy providing the oil keeps flowing.

2) Swap MPFI heads onto the SPFI block and don't install the turbo onto the block. This will effectively give you the hi-comp NA MPFI.

The 4EAT has its quirks, but it will give better highway fuel ecomomy than the D/R 5-speed...

#11 GeneralDisorder

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Posted 03 November 2006 - 08:11 PM

The 4EAT has its quirks, but it will give better highway fuel ecomomy than the D/R 5-speed...


Really? What's the 4th gear ratio on those? I had no idea!

GD

#12 kayakertom

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Posted 04 November 2006 - 12:47 AM

I would de-turbo the GL-10 by putting in an XT non turbo motor - easiest way to go and you wind up with good power and dependability. The 4eat is a very nice match to the ea82 motor. Just part out the donor GL.

............

I just acquired myself (2) Subies.
The good car - 01/89 GL-10 Wagon, AWD, Auto, EA82T, Bad Motor (hole in block)
The donor car - 10/89 GL Wagon, D/R, Manual, EA82 SPFI, Bad Body (tree fell on car)
So I want to swap the good motor EA82 into the GL-10. What problems can I expect? Both cars are complete.

#13 jeffast

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Posted 04 November 2006 - 12:50 AM

i've ridden in an xt powerd gen 1 wagon the car hauls rump roast for what it is. wouldn't be a bad swap but the wiring was a *************** from what i understand

#14 Numbchux

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Posted 04 November 2006 - 02:45 AM

2) Swap MPFI heads onto the SPFI block and don't install the turbo onto the block. This will effectively give you the hi-comp NA MPFI.


This is what I would do. more power (specifically...torque!) than the SPFI motor, and no wiring hassle. and it'd be a perfect opportunity to put a few new gaskets in there, and new t-belts.

#15 4RnrRick

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Posted 04 November 2006 - 09:24 AM

Slow down guys.....

I DON'T want the car that bad. I got two cars and I just want to make one good one out of them. If the good car stays an Auto - Great, new car for the wife ; But if I have to convert it to a Manual - then it will be sold and hopefully I can make a few dollars in the process.

So with that said I basically only have the parts on hand available. (see first post) I'm just not willing to go source another car or more parts. Plus I really don't want to tear the motor down to a short block and start over.

So I'm just really just trying to figure out if the EA82 SPFI engine harness can support the FT 4wd 4EAT Auto tranny. So far its sounds like its not a plug and play swap - but with some wiring, it can probably be accomplished.

#16 Numbchux

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Posted 04 November 2006 - 10:54 AM

So I'm just really just trying to figure out if the EA82 SPFI engine harness can support the FT 4wd 4EAT Auto tranny. So far its sounds like its not a plug and play swap - but with some wiring, it can probably be accomplished.


no

the engine part of the wiring is pretty different. because the turbo block is MPFI....

BUT, you could take both engines out, swap the MPFI heads from the bad motor, to the good one, and drop it in without the turbo (use the exhaust, and intake plenum pieces that are on the SPFI car).

only parts you'll need are a few gaskets. AND, the wiring will be completely plug and play with this method. just have to mix and match engine parts a bit.


I promise, it'll be an easier job than messing with the wiring harnesses!


having messed a bit with a couple different AT harnesses (neither AWD...), the last thing on this planet that I'd like to do is deal with that, and try to have it work! I'm having enough trouble just keeping the engine working on my swap, and it's got a 5-speed....

#17 GeneralDisorder

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Posted 04 November 2006 - 01:52 PM

the engine part of the wiring is pretty different. because the turbo block is MPFI....


That doesn't really matter. As long as the SPFI portion of the donor harness can be grafted into the power and ignition circuits it will run with the existing fuel system. The MPFI portion does not need to be touched even. It could be left in place (although this will result in a LOT of wires). The real question is if the 4EAT TCU can run with the SPFI harness, and what wires need to be spliced over to the TCU

having messed a bit with a couple different AT harnesses (neither AWD..


If you haven't messed with the TCU based 4EAT, then you have no applicaple experience - just like me. We simply don't know. I beleive it's possible, but someone with experience working on the 4EAT would know better. Ask the new generation section of this board - they would know.

GD

#18 Numbchux

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Posted 04 November 2006 - 03:04 PM

If you haven't messed with the TCU based 4EAT, then you have no applicaple experience - just like me. We simply don't know. I beleive it's possible, but someone with experience working on the 4EAT would know better. Ask the new generation section of this board - they would know.

GD


one of those 2 was the harness for my EJ22 donor. and it was a FWD 4EAT.....holy crap. the other was my EA82 3AT, which had it's fair share of wires, but nothing by comparison.

I certainly think it's possible. but I'd rather build a hybrid high-comp, N/A, MPFI motor, and not have to touch the wiring. than the other way around.

I've never really worked with an MPFI EA82 harness though, just messed with/around a couple at the junkyard...so that's mostly just speculation

#19 NorthWet

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Posted 04 November 2006 - 03:10 PM

Disclaimer: I have NO practical experience in wiring/rewiring the 4EAT. So...

The 4EAT's TCU uses at least one ECU signal, the atmospheric pressure sensor that is built in to the MPFI's ECU. I do not know if this signal exists in the SPFI's ECU.

GD, regarding gearing: The 4EAT is geared for about 2200-2500 rpm at 60-65, approx 1000rpm lower than the 5-speed or 3AT. That big of a reduction is hard for the manual to beat.

#20 GeneralDisorder

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Posted 04 November 2006 - 07:28 PM

The 4EAT's TCU uses at least one ECU signal, the atmospheric pressure sensor that is built in to the MPFI's ECU. I do not know if this signal exists in the SPFI's ECU.


Having just done my third SPFI conversion of a carbed vehicle, I can say with complete confidence that it does not contain a MAP sensor, has no provision for one, and contains no inputs or outputs for one. That's probably going to shoot the SPFI/4EAT combo right in the temple. Won't matter how good the engine runs if the tranny can't shift.

So looks like an NA MPFI conversion is the only combo that will get you an automatic from your availible parts unless you want to build a MAP sensor control board and reverse engineer the 4EAT's MAP input signal....

GD

#21 NorthWet

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Posted 04 November 2006 - 09:36 PM

Having just done my third SPFI conversion of a carbed vehicle, I can say with complete confidence that it does not contain a MAP sensor...

It isn't a MAP sensor. It is an atmospheric pressure sensor, apparently used to measure altitude for minor adjustments (I think the TCU uses it to adjust shift points); this is supposed to be integral to the ECU.

IIRC, the signal is a simple high/low indication, so might be easily spoofed.

#22 NorthWet

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Posted 04 November 2006 - 10:05 PM

The following 4EAT/TCU info is specifically for the Legacy, but may be pertinent for the EA82(t):

The TCU uses at least 3 ECU-related signals, plus a vehicle speed sensor (VSS) signal from the speedometer. The 3 signals are for TPS, engine revolution signal, and atmospheric sensor.

The atmospheric sensor is listed as only applicable to non-turbo models. Further reading on the atmospheric sensor (Legacy related):
http://www.ultimates...ospheric sensor




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