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EA81 Turbo and AT questions


jeffroid
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I have a chance to pick up a straight clean 84 wagon with MFPI turbo and an automatic tranny. It supposedly runs but doesn't drive. I don't know if it's the tranny or the motor that is the problem, but that is kind of besides the point of my questions as follows:

 

How much trouble would it be to end up with a non-turbo MPFI set up in the wagon? I'm understanding I can't just ditch the turbo or the compression ratio would be wrong. I've got spare EA81 shortblocks sitting around - that would fix that problem, right?

 

So, am I correct in assuming that I'd pull the engine, put the MPFI heads on a non turbo shortblock, put everything back in, and get rid of the turbo stuff? If correct, how much trouble with wiring, control modules, etc. am I looking at? In general, is this going to be relatively easy to do?

 

I'd also like to ditch the auto tranny. How much trouble is it to drop in either a dual range 4 speed or five speed? I've searched and read about the 5 speed upgrade from the 4 speed on the EA81, so I know about all that.

 

As for my capability, I'm a half decent at best backyard mechanic and have done a lot of work on my EA81's. I don't know jack about turbos though. I did do a search and apologize if I missed any threads on these subjects.

 

I appreciate any help. I need to decide pretty soon whether to pick up this wagon or not.

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you may as well keep it turbo. here are your options

 

if the turbo or mpfi turns out to be bad you can swap in a carbbed motor, just change out the fuel pump

 

you can swap the turbo top end onto a carbbed bottom end

 

it is speculated an ea82 turbo from 85-86 will work, the motor itself will bolt on, and the engine management systems are very similar if not identical. supposedly all the plug ins fit the same

 

a 5spd dual range can be swapped in, you know the basics, flywheel, tranny mount, driveshaft, diff

 

for the ea81 turbo bl;ock the flywheel from a 5spd will fit, but if you use a carbbed motor or bottom end you will have to grind a way on the bottom of the bellhousing to clear the staryter teeth. but you ca also swap the engine bellhousings too

 

hope this answers you i have myself put 5spds in ea81T, and ea82 motror in ea81, just havent done an ea82T in place of ea81T, but i did convertthe same ea81T to carbureted

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you may as well keep it turbo. here are your options

 

if the turbo or mpfi turns out to be bad you can swap in a carbbed motor, just change out the fuel pump

 

you can swap the turbo top end onto a carbbed bottom end

 

it is speculated an ea82 turbo from 85-86 will work, the motor itself will bolt on, and the engine management systems are very similar if not identical. supposedly all the plug ins fit the same

 

a 5spd dual range can be swapped in, you know the basics, flywheel, tranny mount, driveshaft, diff

 

for the ea81 turbo bl;ock the flywheel from a 5spd will fit, but if you use a carbbed motor or bottom end you will have to grind a way on the bottom of the bellhousing to clear the staryter teeth. but you ca also swap the engine bellhousings too

 

hope this answers you i have myself put 5spds in ea81T, and ea82 motror in ea81, just havent done an ea82T in place of ea81T, but i did convertthe same ea81T to carbureted

 

Thanks for the help. My plan is to get it home (if I so choose) see if the problem is the engine/turbo or the tranny. Best case is if it were the tranny then I'd just swap in a manual.

 

If there is something wrong with the turbo I'd rather ditch the turbo than try and fix it 'cause I'm ignorant in regards to turbos (among other things).

 

If I drop in a carbed EA81 won't the wiring and engine and fuel control systems, and emissions, be a nightmare to figure out? That's why I was thinking I'd stay with the MPFI - everything is already there.

 

I don't have any EA82 stuff laying around. If I put the turbo top end on a non turbo EA81 block, won't the compression ratio be wrong? I recall from searching that the pistons are different - flat or domed vs dished? That's why I figured I'd need to swap the lower ends to ditch the turbo.

 

I REALLY appreciate your and anyone elses responses. All I'm trying to figure out right now is if this is something I should tackle. If I decide to actually try and do something with this car, I am sure you will all get tired of reading my desperate requests for help.

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Thanks for the help. My plan is to get it home (if I so choose) see if the problem is the engine/turbo or the tranny. Best case is if it were the tranny then I'd just swap in a manual.

 

If there is something wrong with the turbo I'd rather ditch the turbo than try and fix it 'cause I'm ignorant in regards to turbos (among other things).

 

If I drop in a carbed EA81 won't the wiring and engine and fuel control systems, and emissions, be a nightmare to figure out? That's why I was thinking I'd stay with the MPFI - everything is already there.

 

I don't have any EA82 stuff laying around. If I put the turbo top end on a non turbo EA81 block, won't the compression ratio be wrong? I recall from searching that the pistons are different - flat or domed vs dished? That's why I figured I'd need to swap the lower ends to ditch the turbo.

 

I REALLY appreciate your and anyone elses responses. All I'm trying to figure out right now is if this is something I should tackle. If I decide to actually try and do something with this car, I am sure you will all get tired of reading my desperate requests for help.

The turbo in and of itself is not much of a problem... it is the lack of low end torque caused by the low CR that annoys most people. The turbo just does its thing to make life more fun in the upper half of the rev range. Turbos also are pretty dirt simple to deal with.

 

And as far as replacing MPFI with a carbureted engine, it is not much of a problem (mostly ditching unneeded stuff) but will make it impossible for you to pass emissions testing. (Yes, Miles, he gets to deal with that.)

 

Regarding CRs, the pistons determine that, with the turbos being dished and the carbs being flat(?). If you put the turbo heads on a carb block you would have the carb CR and MPFI. If you put the carb heads onto the turbo block you would get a dog. :lol:

 

If the tranny is the problem then it probably just needs some maintenance: Fluid change, check vacuum modulator for diaphram rupture, clean-up the governor. If need be, I think I know where to find an AT for it, interim or long term.

 

Remember, you have others near by to help you get this going. :)

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I would change to manual, weather the at is the prob or not! Horrible things if you plan on doing highway driving, they have no torque converter lock out, and 3rd is (or seems cos of t/c slip) even lower than 4th on the 4speeds!

PLus, the HUGE :rolleyes:100hp or so feels like much more with the manual in!

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roid....ea81t is by far the most fun to drive old soob I've owned....at all cost - save the turbo....these vehicles are very rare. From what I hear...the 5spd swap makes the ea81t a totally different beast...good luck...if you have any questions...email me....I'll answer them the best I can.

 

stup

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roid....ea81t is by far the most fun to drive old soob I've owned....at all cost - save the turbo....these vehicles are very rare. From what I hear...the 5spd swap makes the ea81t a totally different beast...good luck...if you have any questions...email me....I'll answer them the best I can.

 

stup

 

Thanks for the good words. I bought it last week but haven't had a chance to get it down to my house yet. I've been thinking a lot about it and definitely want to try and keep it intact. A good friend of a good freind has got a shop up near where I got it from. He has been kind enough to hang on to it until I can make room at my house. In the meantime he is going to try and figure out what's wrong with it. I'm not in a huge hurry and I don't want to pass up the free help.

 

Anyway, I'll get it down here in a week or two and will be back with plenty of questions I'm sure.

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