Heavy Metal Affliction Subaru WRX STi

John Schommer
Thursday, August 02, 2012
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 One of the many reasons to love Forza Motorsport is to feel the rush of adrenalin from going fast. Ever improving your top speeds that are far beyond the legal limit, pushing your car to the extreme and optimizing performance through tuning. For most of us, this is our only opportunity to test our skills, tweak our cars and improve lap or drag strip times.

 

This week in Heavy Metal Affliction we meet Forza community member XBAMBOBEE. Julius B. is a student at St. Thomas College in Minnesota where he is studying Business Administration. He has always loved racing and motorsports in general. For study breaks he enjoys Rivals mode in Forza 4, specifically B Class Time Attack or unlimited drag racing. It helps him get his “whoosh” out, as he puts it.

 

Julius’s real world ride is a 2004 Subaru WRX STi that has seen time at both the drag strip and on-road racing tracks. His STi has been built for speed and as Julius has found out, getting the right tune makes all the difference.

 

In pursuit of building his driving skills Julius spent some time behind the wheel of a Ford Formula car at Brainerd International Raceway via Formula Car Experience. These cars look like an F1 car and stick to the track like they are on rails. Formula Car Experience travels the country providing the opportunity for folks to get some track time in the closest thing to a real race car available to the general public. After driving the Ford Formula car, Julius was inspired to see what his STi could do once unbound from the legal limits of street driving.

 

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Straight from the factory the Subaru WRX STi is an entry-level beast, capable of delivering a thrilling ride. It will also plow through the snow that Minnesota is known for and delivers responsive traction under any conditions. Features like the Driver Controlled Center Differential (DCCD) control how power is distributed to the wheels allowing adjustment to the front or rear. The WRX STi’s boxer motor has a distinctive rumble and plenty of power. But that was not enough for this fella.

 

Julius found the right shop, pulled the motor, and had it rebuilt from the pistons up, increasing the engine output to around 300 horsepower. All that power hooked up well on the street but Julius wanted to see what it was really capable of.

 

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First he took it to Rock Falls drag strip in Wisconsin. Here he learned that there is a lot more to straight-line racing than meets the eye. After a few runs the STi showed it had a capable launch, but suffered from gear ratios that are not optimized to achieve his goal of ten-second quarter-mile times, despite having ample power and traction. The key take away from the drag strip for Julius was the short gear ratios—as found in the stock WRX—hindered his Estimated Times (ET).

 

In addition to his time at the strip Julius and the STi have done some track days. While the Subaru was fast, he learned that his street tune and upgrades were not delivering the kind of confidence inspiring handling a driver looks for when it comes to track time. The most notable flaw was over steering due to a stiff rear sway bar that couldn’t be adjusted at the track. The looseness of the car forced him to drive more cautiously than he would have liked. What he was working to avoid was the rear-end coming around when lifting off the throttle. The street tune just did not hold up at the track, more knowledge on the factors that affect cornering was needed.

 

In further pursuit of the right tune and the knowledge of how different factors affect performance, Julius took the Advanced Car Clinic class at a local technical college. This class involved practical application of driving theory and test and tune sessions to optimize the STi’s upgrades and factory settings. By the end of the course he developed a tune that provided a more gradual and smooth power band that enhanced throttle-input predictability. Julius also learned his brake pads and tires became a weak link after heating up. The testing track at the car clinic was very technical and under heavy braking and higher than normal tire temperatures the STi was hard to slow and drifted uncontrollably.

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Through these experiences Julius has reeled in the STi’s power, making it more tractable. He also knows what components to upgrade next to increase performance to get the car to the next level. As with any car project it will never be done, but by applying the experience of track time he can make much more informed decisions.

 

Current list of upgrades:

 

Engine:

Wiseco pistons, ported heads, modified fuel injectors, Walbro fuel pump, TGV deletes, ACL race bearings, Invidia G200 turbo-back exhaust, E85 fuel, stock turbo (VF39), Open Source tune.

 

Interior:

Defi gauges, JDM seats, 10" Kicker amplifier/subwoofer

 

Wheels/ Suspension

S203 18" BBS wheels, Perrin rear sway bar, Whiteline front sway bar, Endless Zeal coil-over shocks

 

Check out this brief video of Julius and the WRX playing in the snow. The sound of the beefed up boxer is worth hearing. For the record, Julius is just playing around, he is nowhere near stuck.

 

 

 

Here are some more photos to enjoy:

 

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If you have a car that you think is a candidate for Heavy Metal Affliction, post about it in the request for community rides thread. If you would like to discuss, comment about or compliment Julius’s car, do so in the HMA thread.