Custom Builds
Introducing the 2015 Subaru WRX—an exhilarating ride that prompted us to push its limits through rigorous testing. In its stock form, the WRX showcased its prowess, delivering 197.7 whp and 228 ft-lb tq. A closer look revealed an erratic boost curve, hinting at untapped potential. Enter the COBB Stage 1 tune, transforming the driving experience with 223.0 whp and 249 ft-lb. Yet, we couldn't resist fine-tuning it further. The PREracing Custom Stage 1 Tune pushed the boundaries, extracting an additional 7.6 whp and 257 ft-lb, enhancing torque delivery and overall performance.
Eager to unleash these modifications on the racetrack, we embarked on back-to-back comparisons. The results were clear—the COBB Stage 1 tune boosted performance, but the PREracing Custom Tune stole the spotlight, clocking the fastest elapsed time and highest MPH of the day. However, challenges surfaced, indicating the need for better fuel quality and addressing high back pressure. Stay tuned for our upcoming tests, where we explore the gains of transitioning to ethanol-based fuels, unlocking the WRX's true potential.
In 2006, Project Heavy Weapon was born, evolving through numerous versions, each a testament to the relentless pursuit of power. In its initial iteration, armed with an AGP 50trim kit, AEM EMS, and RC750 injectors, it stormed the tracks, reaching 415whp on 92 pumps and 470 on vp110. However, an unexpected encounter with a Perrin EBCS malfunction unleashed "ALL THE BOOST," resulting in a memorable mishap at Woodburn dragstrip.Heavy Weapon's transformation continued with Version 2.0, featuring a DCR Option B short block, Level10 performance automatic transmission, and a Precision PTE6266 turbo. Despite reaching nearly 500whp, transmission issues plagued its potential, leading to a rebuild. Version 2.1 saw significant upgrades to the head, including DCR Springs, Retainers, Keepers, BC oversize valves, and custom Crower cams, setting the stage for a head-to-head battle at Import Face-Off. Version 3.0 marked a transition to a stock 2005 manual trans, and Clutchmasters Race Twin, revealing its horsepower prowess on the dyno. Aero enhancements proved pivotal, boosting speed by 9 mph. Version 3.1 raised the bar further, showcasing an extensive list of modifications, from a DCR 2.4L short block to a custom Twin Scroll T4 sidemount manifold and a Precision PTE6266CEA Turbocharger. With a formidable arsenal, Heavy Weapon continues to redefine speed and power, leaving an indelible mark on the racing scene.
The 2015 Subaru WRX underwent an impressive E85 ethanol conversion, embracing the unique properties of this 85% ethanol and 15% gasoline blend. Contrary to expectations, the switch exhibited only an 18.3% decrease in fuel economy, attributed to the engine's efficiency at lower RPMs. E85's benefits, including knock resistance and cooling effects, made a strong case for adoption, despite the limited bio-fuel infrastructure.In the realm of horsepower, E85 showcased its prowess, delivering a peak gain of 43.5 horsepower and 25 ft-lb of torque. The vehicle's quarter-mile time significantly improved, revealing newfound agility and acceleration. Challenges emerged with rigorous launches at the dragstrip, exposing weaknesses in the rear end, leading to differential failures. Despite setbacks, the WRX's performance in roll racing hinted at the untapped potential of this direct-injected, ethanol-powered beast.
