04 Sti donor car into a 2000 2.5RS sedan
Random things of note off the top of my head:
-I haven't been able to locate radiator brackets for use of a GD rad in a GC chassis. I've seen a prototype and tried to pursue them but the maker decided not to produce them on a full scale. It's not hard to make your own but it would be nice to have some nice looking machined ones.
-I used the ECS(East Coast Swappers) Drive by wire pedal adapter plate. Makes mounting the pedal easy and hassle free - nice piece.
-I recommend using as much from the donor car as you can. Gas tank, wiring harnesses, etc. I used everything I could. The only 2000 wiring harnesses left in the car are in the dome and doors. This cuts down on splicing.
-I used the GD cluster in the GC dash, a little cutting of the dash and it fits fine. There will be open space in the corners, but that doesn't bother me personally.
-The splicing isn't too bad. The lights/horn/wiper motor/dome are pretty straight forward. Some electrical experience is required to splice the ignition stuff on the steering column and HVAC. The HVAC is kind of weird to splice in because the STi uses an auto climate system and it's electronically controlled where my 2.5RS is cable operated. Had my father help me get that all working soundly. I also had some trouble with the doors because my wiring diagrams were not matching up at all. I had to power probe it all and figure it out like that. Not terribly hard just time consuming.
-I used everything: Entire suspension minus the front and rear struts, entire braking system including the ABS pump/hubs/rotors/etc (minus the lines, those all matched up fine, assuming the car you're swapping into had ABS), All wiring harnesses (engine/dash/incabin/bulk/etc), Cluster, Entire longblock with all accessories, 6spd trans with working dccd and all, radiator.. Pretty much an 04 STi wearing GC clothing.. or as close to it as you can get. Tho I would LOVE to get the GD dash and seats into my car eventually.
-There is a unit, I believe for the ABS, that is located near the glove box. This needs to be mounted in a certain position if I recall correctly. Parallel to the ground or something. I'm kind of hazey on this memory so if i'm wrong someone please correct me.
-If you ever plan to paint the car I would highly recommend painting the engine bay first while everything is out of it.
This is all just off the top of my head... there is definitely more tips and advice to help one through the swap process but i'm not going to sit here and write a novel. Any questions I would be happy to help anyone with though so feel free to shoot me a PM! I had a few people on the board help me when I was stuck and I really appreciated it, so I guess in repayment I can try my hardest to pass on the help to others.
A downfall for me on this swap was I didn't buy the donor car itself, I just bought everything off of it through a friend. So I didn't get to see exactly how everything was mounted on the STi. Might sound sort of funny but it would of helped me a lot. To see exactly where/how each sensor is mounted. When I first got the swap done I was in a rush and kind of just zip tied alot of things to keep them secure, which really wasn't a great idea. On bumps you would hear noises from the dash and stuff. And stupid little things like I didn't mount the ambient temp sensor right and the wires were pinched under the radiator so it would work for like 5 minutes until the car started building temps and then would lose signal. Pay good attention during the tear down. Make sure everything behind the dash is nice and tight or you'll get little squeeks or rattles like I did. Take your time or you'll have a bunch of stupid little kinks to work out like I did. But hey, live and learn, and I had a ton of fun doing it all... zero regrets.
(check engine light was on for a gross evap leak.. aka the gas station attendant didn't tighten the cap enough. God I wish we could pump our own gas in NJ)
Right now i've had the swap done for about 3 years.. time flies. I've just been daily driving it so far.. on a stage 2 protune + EWG dumped to atmosphere. I've been saving up parts over these years though and this car is really going to be a beast! I can't wait
(gt3076R kit, tial 44mm dumped to atmos, pe850's, grimmspeed coated/ported tgvs + thermal spacers, gruppe s header, blitz FMIC, element AOS....the list goes on)