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Installing an N/A XT MPFI engine into an RX


TROGDOR!
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So I've seen this done before. I know it's an easy swap. I want to put a nonturbo XT MPFI engine into one of my RX's, since they are easily available, cheap, and very hard to kill (unlike every EA82T I had).

 

So what's required?

 

From what I can guess, I need the following from the donor car:

-Engine, of course

-All intake plumbing

-Y-pipe

 

And I'll need to swap all the belt-driven accessories, since the XT uses a serpentine system.

 

I've heard the electronics are identical- is that correct?

 

Are the exhaust systems the same behind the Y-pipe? Or Will I need to get the center exhaust pipe as well?

 

My time is limited and I'll be needing to drive the car 2 hours back home after doing the swap, and will be needing it to get to school the next week. I need to have all my ducks in a row before I do this. Basically I need to spend ONE day on this and have the car 100% drivable at the end.

 

 

Also, which model engine would be easier to get working? The early style MPFI, or the Spider Intake style?

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  • 1 month later...

So, I did the swap this weekend! I'm glad I got a parts car, because I ran into some extra parts I needed.

 

Besides just getting the XT engine, you need to do the following-

 

Intake plumbing:

-Save all air intake plumbing and airbox from the XT.

-Save as many XT vacuum lines as possible- you won't need them all, but several of the EA82T vacuum lines will be too short

 

Belt system:

-The XT has a keyed crankshaft and crank pulley that the EA82T doesn't have!!

-To overcome this you'll need the ENTIRE belt system from the XT! You need the crank pulley and all belt-driven accessories, as well as the brackets that hold them to the engine. The EA82T brackets won't allow the alternator to adjust tension properly, and the power steering pump end up mounting crooked.

-As this swap was with an engine with no A/C, I have no idea what's required to make the A/C work. Probably will have to use the lines from the XT.

-If you order a new water pump, be SURE to order one for an XT! The shaft length is different, when you put the XT pulley on an L-series water pump, the pulley will be 1/4" misaligned from the crank.

 

Wiring:

-All wiring harnesses match up, provided you got the right year engine. I'd reccommend using an 85-87 XT engine for an 85-87 car, and an 87.5-up XT engine (with spider intake) for an 87.5-up car. This will ensure that the distributor and MAF wiring match. Both the donor engine and recipient car were '89 models in this case.

-The main power lead for the alternator is too small to fit over the lug on the XT alternator. Drill it out a little bigger and it will work.

-I'm not sure if the turbo MAF and XT MAF are the same. I used the one from the XT and it worked fine.

 

Exhaust:

-You'll need a Y-pipe WITH an oxygen sensor, if your car is a year so equipped. The XT one will fit, as will one from any fuel injected L-series. Be sure to check it for holes before bolting it onto the car. :banghead:

 

Mounts:

-Save the pitch stopper and bracket from the XT. It bolts to the trans instead of the engine, as the type that bolts to the engine will be way too long.

-FYI, the XT block has threaded bellhousing bolt holes. No nuts required to hold the top of the bellhousing together.

 

Misc:

-Throttle cable. The L-series one is too long. You'll need the one from the XT.

-Lower water outlet tube. The one from the XT meets the driver's side radiator hose at a different angle than the L-series. You'll need to keep the one that was on your original EA82T. You might be able to get away with keeping the XT one, but I changed mine.

-Leave the power steering lines on the XT engine- the top end of them is shorter and required to fit the pump.

 

-Spare tire: the spider intake gets in the way of the spare, and you'll have to drop it in the trunk. XT's came with a cool vinyl bag for the spare, as well as a hold-down to mount it in the trunk. Save the bag for a nice clean look. The L-series will have bolt holes in the floor of the trunk which you can use to hold the tire in place.

 

And I believe, as they say in Germany... Das ist alles.

 

 

Took me a bit of messing around to get all this right, but when it was all said and done, the engine fired up and ran like a champ on the first try. It runs great- slower than a turbo, but still plenty of pull. Very torquey, this would be a great engine for an off-roader. It can still climb a 5% grade on the interstate in 5th gear without bogging down too bad- and the gas mileage is PHENOMENAL. I'd reccommend this swap to anyone who is fed up with blowing up EA82T's or wants amazing gas mileage out of their car. In the mountains here I get about 32mpg with it, and I've heard on flat ground this engine can hit 36mpg.

 

Only problem I had with this swap is a check engine light. Haven't checked the codes yet, but the car runs great.

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I get 37mpg on the interstate with my RX. good going with the swap tho

 

Well, around here we have something called mountains. :lol:

 

I've never had my Subarus on flat, open roads for more than a few miles at a time, so I have no idea what they're really capable of in terms of MPG. Getting anything up over 30mpg in this town is an accomplishment.

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Pics this weekend. Engine bay needs to be straightened up and cleaned, despite the engine running well, under the hood still looks like a bomb went off.

 

Also will have pics when I install my new goodie to make the car look better. Wait till the weekend for that, it's a secret. :D

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  • 5 months later...

TROGDOR,

ever get pic's of this setup - i'd like to see the intake routing and possibly the vaccuum lines. i got the motor in and can't figure out the intake PCV routing. all i have is an NA EA82 inatke tube (not sure what it's from), but no accessories to go with it (like associated bits and hoses).

 

and - i have no idea what to do with the vacuum lines.

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i just swapped in an XT MPFI into an XT Turbo.

 

having issues - did you ever get pictures of this setup?

what did you do with the waste gate controller...that thing bolted to the droping resistor on the passengers side strut tower behind the air box? it has two vaccuum line connections and two other fittings that i guess are turbo related. i have no idea what this thing is and if it will effect starting, but mine won't start and this aint hooked up! curious what you did with yours.

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  • 7 months later...

I have a car that has the same conversion. After a bit of investigating, I found the check engine light is because the engine did not have a knock sensor (code 22). I added a knock sensor and wired it into the wire harness and viola! No more check engine light!

 

1989 GL-10 Turbo w/ 88 XT non-turbo

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