Now we had a very different project. Previously, I had been thinking we’d spend maybe eight or 10 hours going over the car, doing mostly maintenance work and some small upgrades like better brake pads. Now we were looking at taking out every major mechanical part of the car and the entire electrical system and replacing it. It was easily going to be more like 80 hours of work. (In the end, it was probably that much or more, but I didn’t keep track.)
Standing in the shop with the two non-running cars side by side, we drew up a specific plan about what we were going to end up with. I vowed that I would avoid further project-scope creep by keeping the STi engine stock and not modifying it. The car was to be used at High Performance Driving Event (HPDE) track days, which are driving school events that are not timed, so it wouldn’t need to be crazy fast. And we could do without a full roll cage. Since we didn’t own a truck and trailer and didn’t want to buy one, we would keep the car road legal, but we’d take out as much nonessential equipment as we could.
Some of the things we did might not be practical in your home garage. There are various brackets on the car that hold things like solenoids and sensors. Since those brackets are different between the two cars, we’d cut the two brackets apart and weld them together to make one bracket that fit the older car, but the newer component.
Also, we custom-bent and crafted our own hard brake lines under the hood to make those fit. Oh, and we cut and welded the steering shaft. Later, someone told me we just could have taken the two steering shafts apart and made a hybrid one without welding. Oh, well.
With the engine out of the 2.5RS, we cleaned up the engine bay, and – here’s one of those moments that makes sense at the time, but in retrospect seems like it might have been in the direction of “project getting out of hand” – we decided to seam weld the front section of the car. See, the older chassis isn’t as stiff as the newer one, and a track car should be as rigid as possible. Seam welding involves replacing the spot welds that hold the unibody together with one solid welded seam. Our welding guy needed the practice anyway, he said.
Once the welds were ground down and smooth, the engine bay needed to be painted again. We had the local body shop spray it gloss white. Super clean!
We tossed out a bunch of parts we figured race cars didn’t need, like air conditioning, sound deadening, the spare tire and jack, and the radio.
There’s a saying in the Subaru enthusiast community that Subaru vehicles fit together like LEGO® pieces – all the parts are interchangeable. It really is true; the assembled STi engine and transmission, plus the chassis crossmember that supports them, bolted right into the older Impreza. So did the rear differential and its subframe, the STi fuel tank, and lots of other parts. Mechanically, the swap wasn’t that difficult.