Subiesport Magazine

Building New Engines

It has been a busy few weeks for us at Subiesport. As we put another issue to bed we decided to take a day and take our project cars out to our testing facility. We had all done a fair amount of modifications to our cars so it was time to see how they measured up. My wagon had a new suspension setup and a new clutch, Ryan’s Legacy GT was sporting a new set of coilovers and of course we had the new 2008 WRX project car with to test. It was looking like it would be a full day.

Upgrading a 2007 Legacy GT Turbo

For anyone looking to upgrade the turbo in their Subaru, this is a must-see video! Sean Sexton of Rallitek Performance shares some quick tips that could save you hours in the garage. Of course, swapping a turbo isn't the simplest of jobs, so be sure you have some skills with a wrench before undertaking a project like this: doing it wrong could easily destroy your engine.

We'll have a full step-by-step in a future issue of the magazine, but here's the sneak preview featuring Sexton doing the upgrade to our 2007 Project Legacy GT with an AVO 420 turbo. The new AVO unit is bigger and badder (in a good way) than the Blouch 18G we've been running for the past year. That turbo was great, but for our tastes bigger is better. Of course, to support this larger turbo we'll also be doing a lot more under the hood, that's for certain. More to come!

2008 WRX Update, Better Handling

After driving our new 2008 project car, Nemo, around for about a week now, one thing has become glaringly clear: This car needs suspension upgrades. And not needs in the sense of, I need to because I am a driving junky, it needs it because it flat needs it.

During hard cornering on a freeway on-ramp round-about, we were able to get the car to rock back and forth, while under cornering load by getting our trunk monkey to bounce around in the rear seat. Even tracking straight down the road, the car would undulate over bumps. While this is very comfortable for highway driving, it is no good for any sort of performance situation. Why Subaru decided to tune the suspension for Miss Daisy and not Mr. Solberg is a bit of a mystery. Perhaps they thought that the hot hatch market was getting older, perhaps they thought that we really all wanted a vague and “floaty” suspension, or perhaps they just got a killer deal on springs from Buick. There is help though.

Driving the 2008 WRX and 2008 STI on course

Today we put another issue in the can, well more or less in the can. As I write this MediaSpigot Publisher, Ryan Douthit, is slaving over the “technical aspects” of formatting the files that will become the next issue of Subiesport.

While he does that, I am reflecting on my recent driving experiences, most notably a bone-stock 2008 WRX and a very-modified 2008 STI. While the two are very similar in behavior, one is more akin to Bud light, easy to drink and keep in your stomach, even after you drink a whole sixer; while the other is more like Barley Wine, much harder to stomach, especially after you have had a few.

Now I am not saying that one is more enjoyable than the other, but it shows where tuning can get out of hand. Or rather, how a performance-driving setting can bring out the less-than-stellar qualities in a car.

Subiesport 2008 WRX Project Car

With a new model-year comes a new addition to the Subiesport project fleet. We had our fun with our GD-chassis 2.5RS, and since that car is going back to stock, we needed some fresh blood in our fleet. To that end, we have decided that we need to play around with one of the third-gen Imprezas, in turbocharged form this time. The basic premise of this car is to see what we can do within the frame work of a stock turbo and stock engine.

To see where we starting from, we took the car to Pacific Import Auto in Tacoma, Wash., to get a baseline on their all-wheel-drive, Mustang dynamometer.

Dyno Tuning Preparation

You’ve read every forum and visited every on-line store and in the process spent your rent money, the college fund, and your future retirement on bolt-on Subaru goodies. The point of all this madness is to produce a more powerful platform for whatever your personal performance niche might be: drag racing, autocross, track days, or simply bragging rights. However, with few exceptions, your new parts will produce little power and, in the worst of cases, might actually damage the car without proper tuning.

WRC Brakes: Asphalt vs. Gravel

Brakes are an essential component of any WRC car, and in slowing the car down play just as important a role in boosting overall speed. Quite apart from simply slowing the car, drivers use the brakes to position and balance the car on its approach to corners and to slide through tight hairpins while maintaining engine speed.

Each car’s brake setup is also different for gravel and asphalt rallies, owing to the different demands and usage in each condition.

For an asphalt rally, the Impreza WRC2007s use 366mm AP Racing brake discs at the front of the car and 305mm discs at the rear. These are wrapped by eight-pot AP calipers up front and four-pot variants at the rear. On asphalt there is generally more available grip than on gravel, so more force can be exerted through the brakes without the wheels locking, generating more friction. Speeds are also generally higher, leading to higher loads.

Subaru WRC drivetrain: by the numbers

Where far more than expected meets the eye, we look at the complexities of the gearboxes and differentials used in the Impreza WRC2007, and what goes into making them work:

The Subaru World Rally Team has produced over 100 WRC gearboxes since 1999. Almost 50 WRC differentials have been built since 2004. Each gearbox takes 85 hours to build and costs £75,000. Coupled with the rear differential the transmission system contains over 700 individual components.

Each differential takes 16 hours to build, and costs £20,000. The front and rear differentials share components to reduce costs, whereas the centre differential is unique. Once a gearbox has been built, it takes three hours for the team’s dedicated dyno to run through the complete test procedure before it is used on a rally.