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N/A engine in a Turbo?

Posted: Mon Dec 12, 2005 9:30 am
by MPtyza
OK, since my engine really isn't looking too good right now, I had the bright idea of swapping in an N/A engine to get me by for a while till I can afford another EJ22T or even a EJ20G. Now my question is, in addition to the engine, is the ECU the only other thing I'll need, or is there something else I'm not thinking of?

Posted: Mon Dec 12, 2005 9:34 am
by douglas vincent
You could probably just swap in a NA block and run it turbo, just make sure its intercooled and lowest boost possible. The Turbo ECU is likely (never been proven though) to be less hot that the NA ECU.

Personally, I would give it a shot. If it works, its also most likely to give you 20-40 hp over a stock turbo block at the same psi.

Posted: Mon Dec 12, 2005 9:42 am
by MPtyza
I dunno, I'm on a real tight budget right now, and I need the car to get back and forth to work. I know I can get an N/A engine pretty cheap, so if I can get away with dropping that in and switching ECU's and driving it around that way, I'm all for it.

Damn, now that I think about it, at the U Pull-It I go to, they cut the damn exhaust manifold apart. So, the turbo exhaust manifold will bolt up to an N/A EJ22, right? So if I drop in the N/A engine bolted up to the turbo and manifold and all that, and just wire the wastegate open like I've been meaning to do anyway, I can get away with it, right?

Posted: Mon Dec 12, 2005 5:32 pm
by vrg3
I would say to keep the EJ22T intake manifold. That means you keep the EJ22T injectors and the wiring harness attached to the underside of the manifold. If you also keep the EJ22T MAF sensor, then you can just keep using your EJ22T ECU as well. Whether you turbocharge it or not, it'll work.

Posted: Mon Dec 12, 2005 5:43 pm
by MPtyza
OK cool. Good to know I've got something fairly cheap to fall back upon when the engine finally quits on me. Thanks

Posted: Mon Dec 12, 2005 5:52 pm
by vrg3
Other things to think about:

If you use the NA exhaust setup, it won't clear an EJ22T engine crossmember.

If you use the NA heads, you won't have the oil and coolant supply lines for a turbo.

Posted: Mon Dec 12, 2005 6:15 pm
by MPtyza
Damn, there's always a catch, isn't there? :)

OK, so if I've got the wastegate wired open, does the turbo even spool? And do I have to worry about cooling it? Is taking the EJ22T intake manifold and bolting it onto the NA and dropping that in with the turbo exhaust manifold and turbo setup with the wastegate wired open doable and driveable until I can find a new EJ22T block or engine?

I'm just looking for a cheap option to keep it driveable until I can find the proper replacement parts

Posted: Mon Dec 12, 2005 6:47 pm
by rallysam
Note - If you swap the ECU, check the wiring diagrams. I think there are a couple wires swapped on the NA ECU as compared to the turbo ECU, but search the forum to be sure.

Posted: Mon Dec 12, 2005 7:12 pm
by vrg3
If you wire the wastegate fully open, the turbo will barely spool.

You don't really have to run coolant to most turbos. I'm running a 16G on my car without cooling running through it right now.

You probably should run oil through the turbo, though. Unless you can somehow cap off the compressor inlet and outlet; if you do that, you should effectively keep the turbo from spinning at all, which might make it okay not to lubricate it.

Putting the EJ22T manifolds and turbo setup onto an NA engine and running with the wastegate wired open should do just fine. I personally think you'd actually even be fine with the turbo running (lubricated!) at wastegate pressure, especially if you're intercooled as Doug suggests. The NA block with a turbo ECU should stand up to 6 psi of intercooled boost just fine.

Posted: Mon Dec 12, 2005 7:43 pm
by MPtyza
Hmm, any chance in hell I can get away with wastegate pressure with no intercooler at all? I don't know, I'd kinda rather be safe than sorry there.

Now the compressor inlet, is that the part that the intake attaches to after the resonator part, with the little rubber elbow? Sorry if that seems like a dumbass question, but I'm still kinda new to turbos and all that. I'd really like to not have to find a way to supply it with oil, yet not kill the damn thing.

I'll assume that the head gaskets are different from NA to turbo, so if I were to use the NA block and turbo heads, which gaskets would I want to use there?

Posted: Mon Dec 12, 2005 8:02 pm
by vrg3
Yeah, you'd probably be fine with wastegate pressure without an intercooler. If it were me that's probably what I would do at first. I don't know if it'd be correct to describe that approach as better safe than sorry, though.

The aluminum housing on the front part of the turbo is the compressor housing. The inlet of the compressor is where air goes in (an aluminum elbow on ours) and the outlet is where air comes out (where the pipe that goes to the throttle is attached). If you plug those, you have to figure out another way to get air from the resonator to the throttle body.

I don't know which head gaskets you would want to use. I think they're the same thickness... Maybe Matt Monson would have a good suggestion.

Posted: Mon Dec 12, 2005 8:50 pm
by Matt Monson
You will want to use the turbo headgasket. They are the same thickness, but the coolant locations are significantly different on the NA vs turbo heads.

What I would do is just swap in the NA block for the turbo one. Your CR will be in the 9's, but with 8psi non-intercooled, it shouldn't be an issue. I say go for it.

Recently there was a thread from a member who had his engine go on him. When he got in there he found that someone had previously replaced the turbo block with an NA one. He was driving around like that for who know's how long and didn't even know it...

Posted: Tue Dec 13, 2005 7:33 pm
by MPtyza
vrg3 wrote:Yeah, you'd probably be fine with wastegate pressure without an intercooler. If it were me that's probably what I would do at first. I don't know if it'd be correct to describe that approach as better safe than sorry, though.
Yeah, sorry about that, I never finished the thought there. I meant that I probably would just keep the wastegate wired open instead of screwing around with boosting the NA block. sorry about that.

Posted: Thu Dec 15, 2005 3:09 pm
by MPtyza
Well, it's official, I'll be swapping in an NA engine, and I'm going to get it Saturday morning at the U Pull-It. Now, does it have to be an EJ22, or can I get away with an EJ18 if I have to? Would the EJ22T intake manifold line up on the EJ18 heads? Also, is everything under the intake manifold on the Impreza EJ22 the same as the Legacy version? I don't see why it wouldn't be the same, but I just want to be sure before getting something. Since I need a transmission anyway, we'll be grabbing the engine and transmission as a set.

Posted: Thu Dec 15, 2005 4:46 pm
by douglas vincent
ej22 only.

only get a 90-94 legacy

Posted: Thu Dec 15, 2005 5:06 pm
by MPtyza
ahh, ok then

Posted: Thu Dec 15, 2005 5:13 pm
by sammydafish
vrg3 wrote: You probably should run oil through the turbo, though. Unless you can somehow cap off the compressor inlet and outlet; if you do that, you should effectively keep the turbo from spinning at all, which might make it okay not to lubricate it.
That will most definitely not work, the turbo will still spin (though not nearly as fast as when under boost) and the bearings will wear out in short order, plus any residual oil in the bearing will become ridiculously coked rendering the bearing useless.

vrg3 wrote:If you use the NA heads, you won't have the oil and coolant supply lines for a turbo.
can you swap the unit that supplies the oil onto the N/A head? It has a plate on it where the oil lines for the turbo go. I never had a need to try, so I dunno if it will work.

I assume you'd have to swap the oil pan also... not sure when the drain goes but I'd assume there.. I don't own a turbo car... well... not a factory one :)

Posted: Thu Dec 15, 2005 5:29 pm
by MPtyza
wait, why exactly will the EJ18 not work? Does it have the single port exhaust like the newer EJ22's or something? I'm just trying to keep my options open when I go

Posted: Thu Dec 15, 2005 6:40 pm
by Legacy777
MPtyza wrote:wait, why exactly will the EJ18 not work? Does it have the single port exhaust like the newer EJ22's or something? I'm just trying to keep my options open when I go
Personally....I think it'll work. The EJ18 does have the dual exhaust ports. I don't think the intake ports are going to be different, however Matt Monson would probably know for sure.

Posted: Thu Dec 15, 2005 6:41 pm
by Legacy777
sammydafish wrote:
vrg3 wrote:If you use the NA heads, you won't have the oil and coolant supply lines for a turbo.
can you swap the unit that supplies the oil onto the N/A head? It has a plate on it where the oil lines for the turbo go. I never had a need to try, so I dunno if it will work.

I assume you'd have to swap the oil pan also... not sure when the drain goes but I'd assume there.. I don't own a turbo car... well... not a factory one :)
The return line is in the head itself.

Pics of the ej22t heads
http://www.main.experiencetherave.com:8 ... s/ej22t/09

Posted: Thu Dec 15, 2005 7:14 pm
by douglas vincent
I thought you were referring to the OLD 1.8s, I was wrong.

Posted: Mon Dec 19, 2005 4:01 pm
by vrg3
Junior - Thanks for the advice. I stand corrected.

I don't know anything about whether you can swap the turbo oil plumbing onto the NA head. Like Josh says, the oil drain actually goes into the head as well; the oil pans aren't different between turbos and non-turbos.

Posted: Mon Dec 19, 2005 7:31 pm
by Matt Monson
Actually,
running an Ej18 might be kind of fun. My only concern would be overfueling it at idle. I don't know if the readings from the maf would scale back the injectors for you. If you were going to use one, you would want to use your Ej22T intake manifold. Actually, you will want to use this anyways, even if you get an Ej22E

And there are bosses on the NA heads for the turbo oil return, but you would have to machine them out and tap them to screw in the bango bolt. Probably more trouble than finding an alternative oil source for the turbo...

Posted: Tue Dec 20, 2005 2:54 pm
by MPtyza
Well, the EJ18 and the transmission attached are out and waiting for me to install into my car. I can't do anything with it until next Monday though, so until then, I have no car :(

Got a good deal on the two though, since i know the guy that works the window at the U Pull-It . Should have been $160 for all I had, but I got it for an even $100 :)

I really do hate to put the damn 1.8L in there, but it's only to get by until I can afford to get another EJ22T or a EJ20G, so I do have every intention of dropping a turbo engine back into it.

Posted: Tue Dec 20, 2005 2:58 pm
by MPtyza
Hey, I just thought of something. If the EJ22T injectors may overfuel it at idle, would putting in EJ22E or the EJ18 injectors solve this problem?