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Discussion Starter · #1 ·
So I’ll be honest. I’m not a mechanic in any sense of the word. I have a lot knowledge in theory, but I have yet to use a lot of it in practice. I’ve been wanting to get a project car for a while and the a GC8 sti swap is literally my dream. I understand the complexity and cost of an engine swap, but I guess my question is if it’s possible for a noob mechanic. I won’t start off with swapping the engine, that will most likely come much later. I would start will everything I can do before the swap in order to gain as much knowledge about the car. Honestly, even thinking about doing it may be ridiculous, but I’m curious what others think!
 

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It’s doable. Taking out an engine is not as hard as you think especially in these cars. As stalkergc said, leave the wiring to the professionals if you are not experienced at all. Make sure to label everything.
 

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Discussion Starter · #4 ·
It’s doable. Taking out an engine is not as hard as you think especially in these cars. As stalkergc said, leave the wiring to the professionals if you are not experienced at all. Make sure to label everything.
I don’t quite understand the whole wiring situation. It is just combining the old interior harness with the new engine’s harness? And if so, does that mean you have to replace the new engines harness or is there a way to merge the two? I’ve heard you have to replace it.
 

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I don’t quite understand the whole wiring situation. It is just combining the old interior harness with the new engine’s harness? And if so, does that mean you have to replace the new engines harness or is there a way to merge the two? I’ve heard you have to replace it.
It’s a harness merge with the engine harness and the RS harness. Car runs under engine ecu but everything else is basically RS.
 

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2000 2.5rs coupe, 02 wrx engine & 05 dash swap
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That's a tough question which is very subjective to the individual. As for me, my RS was my first car when I was 16, I learned everything I could from the forums and did all the other mods before the engine which built my confidence in what I felt I could do. By the time the original motor took a dump, I had gained much more knowledge of the chassis and was able to confidently do a wrx engine and dash swap.

When doing a wiring harness merge, it can be a bit intense. You are essentially taking the donor bulkhead harness(the wiring harness that sits behind the dash) and you are cutting it open and extracting all of the wires that travel from the ecu to the engine(and maybe some misc. wires) and transplanting them into your gc8 bulkhead harness. There is a very good write up by Brydon that demonstrates this, if you want to do it yourself.
EASIEST option would be to send your two harnesses to IWire and pay to get them merged, that way wiring is all plug and play and you just have to worry about pulling the engine.

If you're going to do a dash swap then you can actually leave the bulkead harness intact for the most part, but you have to modify the new dash beam to bolt to the gc8 chassis as well as make the new hvac fit. And to top it off you have to splice new connectors for the headlights, fog lights, corner lights, turn signals, tail lights, doors/locks, window controls, roof and trunk light.

I guess the moral of the story is take time to learn your way around the chassis and tools and in time you can have the confidence to tackle the project, especially if it's your dream car, it's worth the time.
 

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Discussion Starter · #7 ·
That's a tough question which is very subjective to the individual. As for me, my RS was my first car when I was 16, I learned everything I could from the forums and did all the other mods before the engine which built my confidence in what I felt I could do. By the time the original motor took a dump, I had gained much more knowledge of the chassis and was able to confidently do a wrx engine and dash swap.

When doing a wiring harness merge, it can be a bit intense. You are essentially taking the donor bulkhead harness(the wiring harness that sits behind the dash) and you are cutting it open and extracting all of the wires that travel from the ecu to the engine(and maybe some misc. wires) and transplanting them into your gc8 bulkhead harness. There is a very good write up by Brydon that demonstrates this, if you want to do it yourself.
EASIEST option would be to send your two harnesses to IWire and pay to get them merged, that way wiring is all plug and play and you just have to worry about pulling the engine.

If you're going to do a dash swap then you can actually leave the bulkead harness intact for the most part, but you have to modify the new dash beam to bolt to the gc8 chassis as well as make the new hvac fit. And to top it off you have to splice new connectors for the headlights, fog lights, corner lights, turn signals, tail lights, doors/locks, window controls, roof and trunk light.

I guess the moral of the story is take time to learn your way around the chassis and tools and in time you can have the confidence to tackle the project, especially if it's your dream car, it's worth the time.
What mods did you do before the swap? I plan on getting a wrecked 2004-2007 sti with an EJ257, so I would have to commit to buying the donor car if I really wanted to do any major modding.
 

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2000 2.5rs coupe, 02 wrx engine & 05 dash swap
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A lot of the basic mods that got me comfortable with putting my car on jacks as well as crawling under. Radio speakers and subwoofer were first, then basic mechanics like intake and exhaust. Then springs and struts, sway bars, 4-pot brakes, v2 wrx seats then v5 sti seats, jdm tail lights, replacing all 4 wheel bearings before doing the swap.

Having a whole donor car would be the ideal way to go, you can use all the drivetrain get the upgraded brakes. I wouldn't use sti struts tho from a GD. I've tried them and the valving is a bit bumpy for our lighter chassis.
 

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Discussion Starter · #9 ·
A lot of the basic mods that got me comfortable with putting my car on jacks as well as crawling under. Radio speakers and subwoofer were first, then basic mechanics like intake and exhaust. Then springs and struts, sway bars, 4-pot brakes, v2 wrx seats then v5 sti seats, jdm tail lights, replacing all 4 wheel bearings before doing the swap.

Having a whole donor car would be the ideal way to go, you can use all the drivetrain get the upgraded brakes. I wouldn't use sti struts tho from a GD. I've tried them and the valving is a bit bumpy for our lighter chassis.

Huh. Well from what I’ve heard this would be a dope project, especially for someone like me who isn’t a mechanic of any sort. I just got to find a clean gc8 for sale, not many good picks in Washington at the moment.
 

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2000 2.5rs coupe, 02 wrx engine & 05 dash swap
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They are great project cars considering that they can go together like Legos and you can avoid any drilling or cutting if you keep the original dash. Definitely check for rust in the quarter panels, it's very common especially in syates that actually have weather. If you're looking to keep the car a long time, might be worth looking at California for a rust free car.
 

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Discussion Starter · #11 ·
They are great project cars considering that they can go together like Legos and you can avoid any drilling or cutting if you keep the original dash. Definitely check for rust in the quarter panels, it's very common especially in syates that actually have weather. If you're looking to keep the car a long time, might be worth looking at California for a rust free car.
I live in Washington so rust isn’t a MASSIVE issue, though we do have our share of wet weather. I look on craigslist and FB marketplace but most I find are either sedans or 10k. Yikes
 

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98RS, 98RS, 99RS
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Your best bet is to find one elsewhere in the US and have it shipped to you. Prices of subarus in the pacific northwest are completely obnoxious and overpriced. You can get a comparable car for half the price on the east coast.
 

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Prices will probably still creep up from there for RS's. Get your self a 97+(for the update headlights/grill) L unless you must absolutely have to have the sun roof. You can get a hood/scoop from an impreza outback and RS sideskirts are easy to find. The front bumper is going up in price but all that can still be obtained for 6-8k or better if you shop around.
 

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There are definitely more things to change and slight fabrication needed if you choose 95 or 96 L, although I remember reading that 97 was an odd in between year so I can't say for certain what differences there are but 97+ would be more ideal.
 

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There are definitely more things to change and slight fabrication needed if you choose 95 or 96 L, although I remember reading that 97 was an odd in between year so I can't say for certain what differences there are but 97+ would be more ideal.
What fabrication are you referring to? And yes 97 is a transition year with a mix parts, there's a handful of differences that's been pretty well covered on here. 97 they is the first year of the face-lift, has the 96 dash, but with the newer hvac controls could in the 98+. Charcoal canister may be different (pre-96 style), rear abs sensor reads the tone ring mounted on the axle and not the hub. If doing a full sti swap, pretty much everything can be swapped out and rear hubs have to be swapped to fit sti rear diff/axles/brembos.

O and 97/98 have fluted headlights vs the crystal head lights found on 99+. Same shape to match the face-lift hood and grill, but doesn't have the crystal clear lens.
 

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What fabrication are you referring to? And yes 97 is a transition year with a mix parts, there's a handful of differences that's been pretty well covered on here. 97 they is the first year of the face-lift, has the 96 dash, but with the newer hvac controls could in the 98+. Charcoal canister may be different (pre-96 style), rear abs sensor reads the tone ring mounted on the axle and not the hub. If doing a full sti swap, pretty much everything can be swapped out and rear hubs have to be swapped to fit sti rear diff/axles/brembos.

O and 97/98 have fluted headlights vs the crystal head lights found on 99+. Same shape to match the face-lift hood and grill, but doesn't have the crystal clear lens.
These are if you are using a 95/96 L as a base for the swap. It’s not much but there are some little things that has to be done here and there to get things to fit.

Airbox cutout is different so that has to be cut a bit to fit the new airbox since cutout orientation is slightly different.

The tabs on top of the transmission tunnel where it bolts is also different. Have to grind the back so you can get the vent and heater core to fit.

The circle where the steering column passes through is also different. Bigger in the later year. If they want to upgrade the dash/interior then will need to use a new dash bar but the mounting for the steering column is different on the 96/96 compared to later year. The later year uses a skinner shaft with a bigger bushing where it passes through the firewall vs. 95/96 was the opposite. Will have to figure out how to adapt this if want to upgrade the dash.

Dash mounting is also different and is not a direct swap. Black tabs where it goes through the dash is different and 10mm bolt where dash mount on later year does not mount to 95/96 mounting hole. Will need to make your own bracket or leave as is.

No hood latch mounting, need to make your own bracket if using new dash.

95/96 also did not come with an evap system. This is plug and play and no real fabrication needed but just a lot of things to run. Could possibly delete but not sure how happy the ECM will be.

Wiper motor mount is different, had to cut off some wiper motor arms on later year to get it to fit rather than splicing old 95L connector.

My 95 didn’t come with ABS but I chose to add back in ABS so had to make my own lines but this is optional since seems people delete it.

There is some more but some stuff that I can remember off the top of my head
 

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O ok sounds like your talking about a gd dash swap which yes then there is a lot more you have to do, but OP just said full swap so I was referring to drivetrain which does not need cutting all the chassis are the same.

For the airbox do you mean to go in to the fender? Just omit it, it's a silencer that quiets down the turbo sounds.

You can just reuse the wiper arm and motor, I just spliced my connector and it works like normal. Wiper speed is all handled by the switch on the steering column.

The tabs on the trans tunnel is the same for our chassis, but I was able to force the heater core in w/o cutting but it was not easy.
 

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The dash beam needs either new holes drilled to mount to the car or cut and weld the endplates off the old bar to the new beam. If you opt to drill new holes in the endplate, the gd dash beam has the mount for the hood latch release.

This is the first time hearing about the steering column tho (haven't swapped an older chassis yet) do you have any pics?

Sounds like you had quite the project too, what dash did you put in?

The circle where the steering column passes through is also different. Bigger in the later year. If they want to upgrade the dash/interior then will need to use a new dash bar but the mounting for the steering column is different on the 96/96 compared to later year. The later year uses a skinner shaft with a bigger bushing where it passes through the firewall vs. 95/96 was the opposite. Will have to figure out how to adapt this if want to upgrade the dash.
 

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My project was a complete 99 RS (minus the sunroof) into a 95L swap so these are the specific noticeable difference. I did save the whole RS roof by cutting from the pillars if I ever feel the need to put it in in the future. The RS body was beyond repair living in the northeast and since we only picked it up for about 1,500 a swap into a cleaner L was the cheapest alternative I can find but will be using this as the base for a potential wrx/sti swap in the future.

The airbox where the ac line connects to the firewall is a slightly different orientation. One orients more diagonally vs horizontal so it has to be cut so you can mount the airbox. Obviously if this is a drivetrain only swap than not necessary but both heater core and airbox is different between the earlier model vs later year and you can’t use one without the other.

Trans tunnel tab are the same shape but where it sits is different between the two. If updating dash then the tabs will not line up to the dash beam mount.

The steering column mount to the dash beam is different so if they want to do a dash swap then they have to use either a steering column that is made for that dash beam or adapt the L steering column to fit swapped dash beam. If one decides to use the corresponding steering column that fits the dash beam then the other problem is the steering column bushing in the firewall since the shaft diameter is different and also the firewall hole is different. I don’t have a picture of this but what I did was use everything from the 99RS but drilled out some poly bushings to around 38-40mm so it fits around the shaft kind of as a spacer so I can reuse the old 95L steering column bushing that passes through the firewall. This is the only picture I have of the two steering columns where you can kind of notice the difference but might not be as clear.

I guess overall message I was trying to convey is that an earlier year 95/96 L coupe may need a little more things done to get things to fit even though chassis is the same it is a bit more nuanced compared to a later year chassis.

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