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turbo swap into 88 SPFI 4wd d/r Wagon

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well, here i am at jims after driving some 100 miles with no front axle and half a brake system...


we got the xt and the wagon over to the garage. ithe wagon had add-on ac, and it works. so we are going to have to switch all the bracketry and pulleys from the spfi to the turbo motor for use in the wagon.


also, the pitch bar mounts are going to have to be swapped. the wiring harness for the mpfi on the xt goed into the firewall, so it is separate than the headlight/charging harness. but the fender will have to come off for the knock control unit, for the 86 style mpfi


the wagon will keepf its spfi harness, so it wont have to be separated from the headlight/charging harness.. i would like to mount the mpfi ecu under hood, for swapability if the motor went into something else. that way, it could take the spfi motor back plug and play.


the only thing i would have to figure out id how to trigger the fuel pump. i would like it to read off the distributor, like the spfi crank angle dist does. but turbo mpfi is an 86, which has a mechanical distributor.

iif i dont figure that out the pump will come on with the key in run positiion, or better yet, kick on with the tachometer(which would be on with the distributor thru another circuit.


we will also swap the rear trailing arms, it will make the disc swap easier, but the idea is it will allow for use of the xt rear swatbar, which the wagon doesnt have. aso the fron tswaybar will be swapped.


the turbo axles will be swapped into the wagon, they were from an automatic, so they will fit the 5 speed.


we may consider swapping the whole entire strut/axle/hub assembly in one piece. ot will save some work and not risk boogering the axle threads.


swappin xt seats too!


the downpipe off the turbo will bolt right in to the wagon's midpipe, as does the y pipe in my turbo wagon(carb spfi block) fits its existing exhaust.


this is what i have come up with by looking. more to come tomorrow!

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there's a whole case in the fridge. savin it fot tomorrow:drunk:


we'll start by puling the hrness from the xt, then the motor. then strip the motor down of its pulleys and anciliaries.


then out comes the spfi, then all the pulleys from it goes to the turbo, and then the flywheel swap. then goes in themotor, then the turbo harness. get it running, then suspension swap!


then the xt can sit there like a pile of crap, because it has no title(its a shame, because ite real nice!)


if i land the xt6 in butler(rough and doesnt run), and get the title, swap the dashboard and call it registered!

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so let me know when you come to indy. where i am at tonight is equidistant to indy and where i live


as i ponder, i wonder what would be a good way to wire the ign pulse signal to the spfi's ecu to kick on the fuel pump? leaving all the spfi stuff intact, so it will work the same with the absence of the turbo junk. i really dont feel the need to pull the carpet up, although the seats will get swapped.

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got most of the inside of the xt apart. what was subaru thinking? that xt was pput together in a way that i swear subaru shoved elves in the dashboard to put the screws in, and the elves had to find their way out thru the seams between the plastic!


i had to pull the center console, during which i pulled the seats to get to 2 screws(seats were coming out anyway)

i had to pull the whole dashboard, after getting the steering column out. i dont understand why you would have to get behind the radipo to pull it out, its still in the dash with impossible screws.

keep tearing apart to then find out the ECU is in the Trunk! but its not a waste, because i need the wiring up to the firewall and engine. alleyboy is getting the dashboard anyway.


back to work, gotta get the whole bizzle

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I have the ecu and its wiring harness out and cleaned up. i just finished pulling the knock control unit(86) i grouped the wires and taped them up. the green clip is still there, i will leave it until i find what to wire to. i have the haynes book for a diagram, some of the colors are different than in the book, but i pretty much know what's what.

the ecu has its own fuel pump clip, so i will disconnect the spfi's and use it. i will most likely mount the whole unit under the rear seat in the wagon.


next comes out the xt motor, then the wagon goes in, and out comes its motor. after swapping brackets and the flywheel, i will connect the ecu and get it running before i make my final connections and installation.

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i thnk the haynes and chiltons only have the wiring for the hotwire. i have been runing into colors not matching on my 85 harness. let me know if you find the correct diagram, cuz im in the middle of the same thing.

your going to use the ecu as a stand alone motor only controller right? not swapping the whoole harness in?

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the ciltons book we had didnt have squat. the haynes book has "typical 84 thru 86 mpfi" and 87-84 mpfi


one of the wires was labelled brown with black stripe, but the hrness had brown with red stripe. it was the oly brown wire on both the schematic and the harness.


yes, it will be standalone. it will run of the spfi coil, but the little dookiet on the bracket will be disconnected. i will wire it up to get it working, and then instal it. if i dont have time to install it, it wil go in the spae tire compartment and connect directly to the battery. but when id does install, it will come in thru the grommet on the passenger firewall, down along the rocker panel, and under the wagon seat. the clip off the ecu will plug into the fuel pump, and the spfi's will hang. all of the spfi connections under the hood will hang too, maybe tape off the connectors and tuck them away, but leave them un-messed with


we got as far as having the xt motor out, and the spfi motor out.

originally we were going th leave the add-on air conditioner in tact, but the spfi had the long water pump and the xt had the short water pump, and we didnt have the short pump v-pulley required to do so. so we decided to sacrifice the ac for not having to swap water pumps.


but we had a problem. the xt flexplate bolts were on super tight, slightly rounded. we got 2 out, but we risk tearing up the bolts too much trying to use 12 point 3/8 dr sockets, and the one 6 side socket we used split on the first try.


we amde a last ditch efor to go to walmart for a socket, but hey either had 12 point metrics or 6 point standard, in sets, none would do any good.


so we were considering just resealing the spfi and put it back likeit was.


but here is the dilemma. the spfi pukes oil, like it is under pressure. jim has cam cover gaskets and an oil pump gasket. the oil leaks onto the crossmember right next to the motor mount hole, which looks to me to be leaking out the o-ring on the cam box where it meets the head. when she runs she has a steady "pour" loke when you dump the last little bit of oil out a quart bottle


so tomorrow we are going to go get a good socket, and 1/2 dr set. we need to get at least one motor onthe car and running, but it would be pointless to get the spfi back in if we dont have the o-ring.

and if we were to do the rear seal, we would need the socket to pul the flywheel anyway. so in the effort we may as well go with the turbo engine afterall


i told jim it was his call, and he said "get one of those motors in" so its up in the air at this point

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Actually, if the turbo is a 3sp auto, they will fit..


All NA = 23 spline

Turbo 3AT = 23 spline

Turbo 4EAT = 25 spline

Turbo Manual = 25 spline

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well you guys, this weekend was a total disappointment.

the bolts to the turbo's flexplate are too chewed up. we got 4 off, but the others are on so tight that an impact wont take them off with 125 pounds of air, and are too chewed up for the breaker bar.


we decided to fix up the spfi and put it back in. what i thught was a bad o-ring on the cam box was actually a crack in the cam cover sealmthat was 1.8 inch wide. that was the caise of the major oil leak.

then while doing the water pump, the one jim got from napa was the short one, but the one on the motor was the long one. the one on the motor was still in working order, but was probably on its last leg and wouldnt survive the winter, motor has over 180,000 miles. so we used the leftover one from his 80,000 mile turbo wagon


so we did the rear seal and the oil pump seal, jim didnt get cam seals or front seal, but they look good enough to make it thru wintr.


we put the new clutch on, but had a hell of a time trying to get the motor to line up. the kit came with some odd non subaru throwout bearing, and since the motor wouldnt mate, i had a speculation to pull the clutch disc and see if it fits.

nope. the hole was too small, probably for an ea81 or 2wd ea82.

maybe it was for something else alltogether with the odd htrowout bearing, 2 strikes out of three. the pressure plate fit though.


i told jim to take te lutch set back and ge his money back. the clutch in the car had a fairly new throwout bearing and presure plate and clutch. that clutch still has more than half its life left to it.


so we get the spfi running, no more leaking where it did. but i saw a big pudle on teh floor. i took a look under and part of the mickey mouse gasket is protruding out the bottom of the oil pump. i wa slike wtf. that is the irst time i messed up on a oil pump seal. it must have fell out of lace during the install.


we never did get to the axle or the rear brake swap.


at least the spfi is driveable so i can be moved or parked elsewhere(jim has 7 soobs ain his drive!) but the xt is undriveable and half parted out in vain.

the turbo motor is there with all its ecu wiring, if it werent for them damn bolts!


i wouldnt call it a failure, but it was by no means successfull. maybe another day.


i am going to have to come back and finish the ales and brakes, and fix that oil pump :banghead: :banghead: :banghead: :banghead:

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