Turning a Rally Car into a Track Car - 2004 WRX Build

The Goal

We need to increase the number of track cars here at The FIRM. For HPDE classes, Corporate Events, and (possibly) Open Track Day rentals; we need more cars and more options in our pool of cars. As much as I’d love a fleet of GT3’s, it’s just not in the cards. They don’t have to be supercars, but they need to be fairly quick, reliable, and inexpensive. Yes, all three: Quick, reliable, AND inexpensive. It can be done!

The Problem

In a nutshell, crazy prices. The cars we use for our HPDE classes have consisted of Mazda Miatas and Nissan 350z’s. We’ve been looking to add to our fleet for the last year, but as everyone knows, the car market is Covid-Crazy. Three-year-old cars are selling for more than new. 30-year-old Miatas, which would have been $2500 in early 2020, are suddenly $5000 and are barely road-worthy. So while we are still looking for a new-to-us NB or NC Miata, and another 350z, we needed to find another option that wasn’t twice our budget.

The Solution

I was all in for a C6 Z06 Corvette, but I was quickly reminded that this was supposed to be a budget-conscious build. So, the next best option is a free car. Free? Yes, free. Sort of. We have a few class rally cars here that have not been used for a while, so why not convert one to a track car?

The Base

We have the base covered with a 2004 Subaru WRX (not an STi, unfortunately) that has been part of the rally car fleet for over a decade. In a normal car market, this would fetch about $4000. That price certainly fits in the realm of a budget track car that could easily be driven to and from the track.

Stage 1

We will be removing the old wrap (note to anyone reading, do not let a wrapped car bake in the sun for years), and essentially return it to stock. We plan to start with as basic a build as possible and see how it does. To begin with, we have just a few upgrades planned. Nothing too expensive, and nothing but the essentials. We will build it just like we would recommend to someone building their first track car. First and foremost, are some cosmetics and then cooling. A boosted car in the Florida heat needs some help over and above the stock top-mount intercooler.

Here we go – planned upgrades for Stage 1:

- Strip the wrap and give it a satin-black paint job
- Upgrade to a front-mount eBay intercooler
- New KYB OEM-style struts (years of rally killed the OEM struts)
- Whiteline lowering springs
- Hawk Performance Brake pads and 600 Brake Fluid
- 3” Cat-back exhaust (haven’t picked one yet)
- 17” Wheels
- 200tw tires (RS4? Conti? Accelera?)

Everything else will be kept as-is for now. We will use it in our HPDE classes, ride alongs during Open Track Days, and we may even run it in our Time Trial events. At the start, it should slot right in as a TT5 car. As we progress, it may move up to TT4 and have a big challenge ahead for it!

For now, though, we will run it a to see what needs the most attention to get to the next level. We will be tracking and reporting all of the obvious data like lap times, brake temps, tire usage, water temps (it is a turbo car after all), and whatever else we see as pertinent.

Stage 1.5

Who knows what the second round of upgrades will be. Our initial discussion has been around the suspension. Coilovers and sway bars are the obvious upgrades… Racing Seats? Harnesses?