Swapping a JDM LGT (2.0GT) engine into a USDM LGT (2.5GT)

Hey guys. I've been wanting to do an H6 swap for a while. But show season is coming up real directly and I need the car running until I can have a full swap prepared. So I am going to put an LGT specific engine back in. I sold my longblock and do not have one. A place here in FL has JDM engines and they happen to have a 65k mile longblock from a JDM 2.0GT for a relatively inexpensive price.

 

Everything looks to be plug and play, including the intake manifold. The only thing I would need I change looks to be the wire harness to a USDM version. There are a few extra sensors I see like the lower sensors by the valve cover. I've never seen those on anything USDM. I'm not exactly sure that those would matter if I didn't connect them.

 

As long as I get a new engine harness for my 2.5GT, I should be able to use that with the 2.0 and have it tuned for the obvious change in compression and displacement, and turbo.

 

So does anyone see any reason why this wouldn't work?

You may want to ask Paul at AVO World, he might know what issues you may come across.

If for whatever reason, it's going to be a whole swap like ECU and wiring and everything, I'll just stick to the original H6 plan. Haha

I would think having extra things from the 2.0 not hooked up would not cause any problems. But the USDM ECU is going to want all the US connections.

 

I know its a show car, but put yourself thru all the hassle of swapping engines, just go buy a 3.0R car and fix that for the show.

 

IMO your wasting money. A much better swap is the K swap into a 92-95 Civic, or a B series swap. Easy 10 second car. Sorry, show is nice, IMO, go is much more fun.

 

I don't understand why you'd want to do a swap with this big of a 4 door car. I'm a realist, I'd rather have a quick GT and a fast race car. Our race car, see avatar, took 2nd place in a car show once, before it was even a full race car, it was only a low 12 second civic than.

 

I've been about all the help I can.

 

Good Luck.

I don't care about having a race car. I want something MORE reliable. I sold my built engine because I didn't need it. My car is slammed and cambered and there is literally no reason that I should have power.

 

I like how my car is. I just want something more reliable engine wise so that I don't have to worry about things consistently breaking.

 

And just going out, ditching mine and buying a 3.0R isn't as easy as it sounds.

 

Back on topic, the connections appear to all be the same and I am not sure that the signals sent to the ECU are going to be different other than what I'd need to tune. So I may try this and order another USDM wire harness and ditch the JDM harness.

And here are the sensors I'm talking about. Look to the bottom left of the valve cover.

http://img.tapatalk.com/d/14/03/22/etesehab.jpg

JDM engine has Quad avcs heads, your USDM doesnt, you will need the jdm engine loom and also ecu. Does it come with turbo and up pipe and headers etc, as jdm block is designed to work with twinscroll setup, could be a whole can of worms trying to get everything functioning properly. also Im sure there is more i dont know about but im not sure its worth the stress or hassle

JDM engine has Quad avcs heads, your USDM doesnt, you will need the jdm engine loom and also ecu. Does it come with turbo and up pipe and headers etc, as jdm block is designed to work with twinscroll setup, could be a whole can of worms trying to get everything functioning properly. also turIm sure there is more but im not sure its worth the stress or hassle

 

 

This might explain those extra sensors. It comes with everything. Even the ECU. So if I swapped the engine harness and the ECU, the chassis, fuel, and other connections can still be made with the JDM ECU as they were with the USDM?

 

In other words, the JDM ECU will hook up to everything just fine? The only difference is the change in the engine harness?

yeah probably the avcs sensor on both the intake and exhaust on both heads. Im not sure what else would be needed. I just know when i was rebuilding mine it was best to keep the heads i have to have it working properly rather than swap to an sti engine. I Think you might be one of the first to try this! Emissions will be higher due to lack of tgv's and also no cat in up-pipe. Also you will need the downpipe with both sections to connect to your CBE. why not just get a used 2.5 US GT motor, surely thats cheaper and is also stronger. JDM blocks are weak compared to US EJ257's wont take anymore power than what stock turbo supplies without spinning a bearing or snapping a rod.

Because this swap is only going to run me $2k AND comes with a trans.

Other than an exhaust, this car will be completely stock.

Go for it so!

I am going to jump on this swap and I'll just use the JDM ECU to go with it.

Please keep us updated and let us know how it works out.

jdm 2.0 > v8

 

 

Sent from my iPhone using Tapatalk

jdm 2.0 > v8

 

 

Sent from my iPhone using Tapatalk

 

Bro, do you even?

 

 

In what way? Did you read this:

 

JDM blocks are weak compared to US EJ257's wont take anymore power than what stock turbo supplies without spinning a bearing or snapping a rod.

 

Which basically means that unless you build the bottom end and hella up the boost, you're not looking at anything fantastic against a V8, and certainly not against the modern V8s of today.

What's funny is I have the opportunity to swap a V8 into my car right now. A 352 big block to be exact. If I want to do that, I'll have to find a trans that will bolt up and a rear end that will allow me to run all the camber that I have with binding axles.

 

I do not wish to have a bell housing adapter made to mate my trans to that engine.

Okay. So I was doing a little bit of thinking. I could remove the valve covers from the JDM EJ20, and swap the quad AVCS cam caps out with regular dual AVCS. So as long as I swap that out, the only differences that I can think of between the two is the obvious displacement and the twin scroll exhaust and turbo set-up.

 

Any input? I am about to hit the order button. Then later this year, I will drop the H6 in.

Bro, do you even?

 

 

 

 

 

In what way? Did you read this:

 

 

 

 

 

 

 

Which basically means that unless you build the bottom end and hella up the boost, you're not looking at anything fantastic against a V8, and certainly not against the modern V8s of today.

 

 

in the way that it's cooler to swap a subaru motor into it than a v8. mine was not a comparison of power, of reliability, or of any practical measure. i just personally think that it would be a cooler build to see finished than a v8.

and yes I read your post this morning..

What's funny is I have the opportunity to swap a V8 into my car right now. A 352 big block to be exact.

 

saw your pic on instagram the other day, that's why I decided to chime in ha. I'm not pretending to have any

motor swapping experience, and I don't have any useful knowledge on the subject, just think it would be cooler to keep your subaru a subaru.

I am no expert, but having looked up the issues of swapping a JDM setup into a RS, I can say the ECU wiring can come back and bite you.

 

Mr.TRis did the following writeup, I would suggest you have a look-

http://legacygt.com/forums/showthread.php/reasons-why-your-2-0-jdm-hellajdm-motor-swap-wont-223230.html

Swapping this into an RS vs. a Legacy are two different things.

Swapping this into an RS vs. a Legacy are two different things.

 

This.

 

There are miles of wiring differences between the 4th gen LGT and and the GC8-style RSs. Much easier to do engine swaps on the pre-'00 cars than the newer ones with all the extra body and safety electronics.

True, but there are signicant differences in where the wires go and to what places. Is the JDM ECU even located in the same area? If you utilize the JDM ECU and wire harness, will all the rest of your car harness fit right in? For the RS crowd, the two harnesses have to be merged to keep all the rest of the stock USDM accessories and lights working properly.

 

I'm just giving you a warning that you might run into these issues, but like I said, I have never done it and have no idea what might be involved, but have researched other JDM Subaru swaps. These swaps I was looking into were for the 99-01 RS to corresponding WRX/STi counterpart JDM chassis models.

 

With the lack of people on this thread even considering the swap, much less gone through the headache of actually doing it, makes me think it is not feasible- especially if you are looking to tear it all out for a H6 (which is awesome!) a few months down the road. To me it looks like you want something quick, easy and cheap to implement to get your car moving for the time being- for that, I recommend a junkyard/used USDM stock setup. If those are hard to find, check you local insurance auction sites for a wrecked car- you might get lucky.

True, but there are signicant differences in where the wires go and to what places. Is the JDM ECU even located in the same area? If you utilize the JDM ECU and wire harness, will all the rest of your car harness fit right in? For the RS crowd, the two harnesses have to be merged to keep all the rest of the stock USDM accessories and lights working properly.

 

I'm just giving you a warning that you might run into these issues, but like I said, I have never done it and have no idea what might be involved, but have researched other JDM Subaru swaps. These swaps I was looking into were for the 99-01 RS to corresponding WRX/STi counterpart JDM chassis models.

 

With the lack of people on this thread even considering the swap, much less gone through the headache of actually doing it, makes me think it is not feasible- especially if you are looking to tear it all out for a H6 (which is awesome!) a few months down the road. To me it looks like you want something quick, easy and cheap to implement to get your car moving for the time being- for that, I recommend a junkyard/used USDM stock setup. If those are hard to find, check you local insurance auction sites for a wrecked car- you might get lucky.

Refer to the link that you posted and you will see my response.

 

It may be cheaper. However, being that this is not a long-term swap, it will be worth paying the lesser amount. Finding a 4th gen LGT in my area in a salvage yard is like finding the needle in a haystack. As far as auctions go, I would at that rate be paying a higher amount than I would if I had just bought the USDM engine itself. I would swap the USDM in if I knew I weren't going to lose money on it. If I sell it for even $200-500 less than what I paid, it will still take forever to sell. I am definitely going to go the more inexpensive route on this one with the very slight inconvenience of doing a little bit of extra work.

 

ALSO, like I said; I will be using the USDM harness and ECU. The USDM harness appears to connect to absolutely everything BUT the exhaust AVCS ports. This will be solved by putting a USDM-spec dual-AVCS, cap in place of the JDM one. And the only other difference is the twin scroll exhaust/turbo setup and the obvious displacement.