legacycentral bbs

This might have been covered before, but I couldn't find a thread.

I have a 98 GT with a rusty roof. Cost to repair is prohibitive.
I have a line on a 91 Legacy L with a loose valve guide, early approximations to have the repair on the head done is around $1000.

Question: Will the EJ25 bolt up and run in the 91 L?

It can be made to run. Is the 91 a standard or an automatic?

Look up Jason Grahn's old posts on his swap.

The 91 is auto, the 98 is also auto.

Guys - thank you for the thread link! You rock!

Unfortunately the swap looks to be way beyond my capabilities - both personally and toolwise.

The fact that it's an auto will make things a little easier, because you don't have the problem Jason had with the IAC valve.

This swap will be very, very easy. All your stock stuff will just plug right into or fit right onto the EJ25. It will hardly be any more difficult than just removing and reinstalling the same engine.

Hmm, well, you give me food for thought.

What problem exactly did Jason have? It wasn't made real clear - it sounded like he had a couple of wires to deal with. And he had to reuse the throttle body because the EJ22 intake manifold didn't fit on the EJ25.

Or was that the problem you were talking about?

I have some local guys around who have removed engines before...they will probably help if I feed them!

I just want to make sure it's completely straightforward, and the car fires up and runs.

Jason saw two problems: one with the IAC valve and one with the throttle.

The IAC valve used on 90-91 manuals is different from the one used on most other Subarus made in the 90s. The IAC valve on the 91 you're looking at is more or less the same as the one on the 98, so you can just use the 98's. So this is a non-issue for you.

As for the throttle issue, you just have to do the same thing Jason did -- keep the 91 throttle body. It will bolt directly up to the 98 intake manifold.

So let's see if I can enumerate most of the stuff you'll use...

Stuff from the 98:

98 engine block and heads
98 intake manifold
98 injectors
98 IAC valve
98 spark plug wires

Stuff from the 91:

91 exhaust manifold
91 engine wiring harness (the one attached to the underside of the intake manifold)
91 throttle body (with throttle position sensor)
91 throttle cables
91 camshaft position sensor
91 crankshaft position sensor
91 intake tubing
91 power steering pump
91 alternator
91 air conditioning compressor (leave the hoses attached and just put the compressor to the side while swapping engines)

Stuff from either:

91 or 98 MAF sensor (they're the same)
91 or 98 coolant temperature senders (they're the same)
91 or 98 ignitor (they're functionally the same)

Special notes:

98 ignition coil pack (91 will work too, but the 98 one is a little better)98 knock sensor (unless it won't plug into the 91 harness, in which case use the 91 sensor)
98 purge control solenoid ((unless it won't plug into the 91 harness, in which case use the 91 solenoid)

I'm doing this from memory, so it's only mostly right... hopefully someone can confirm this or correct me if I'm misremembering the 98 Legacy EJ25. In any case, almost all of the swap will be just installing whichever piece fits.

Alright, so now I need some advice (should I start a new thread?):

Replace head(s) on 91 Leggy - probably cheapest and most convenient option,

Q: What kind of damage can be done to the motor if the valve guide is stopping the valve from closing (sliding into the combustion chamber)?

I don't want to mess with the car too much, I could be buying it for $200.

If this becomes a big discussion it'd make sense to start a new thread, but...

A loose valve guide shouldn't really cause permanent damage on a noninterference engine... The only way I could imagine it happening would be on an engine tuned fairly close to the edge -- the oil contaminating the intake charge could reduce the effective octane of the mixture enough to cause detonation at high load.

If I were in your shoes I'd just swap the head, I think.

I don't know if I should start a new thread but I have a similar question:

Can I swap my block for a 257 short block and just bolt all the rest of the 2.2 engine parts back on?

93Leg-c wrote:I don't know if I should start a new thread but I have a similar question:

Can I swap my block for a 257 short block and just bolt all the rest of the 2.2 engine parts back on?

You can. Your CR will be somewhere in the low 9's...

Thanks Matt. I appreciate your input.

So, will head gaskets bring it back down somewhere where it "should" be or do I have to go to heads with larger volume? If so, what are my options and which would be the best?