A full line of AVO high-performance products developed and displayed in the demo car complement the longblock perfectly. However, nothing expands the capabilities of the engine as profoundly as the AVO550 ball-bearing turbocharger, which is based off the Garrett GT series rotating assembly. The turbine housing and compressor cover are proprietary to AVO, but cooling and shaft support is the highly reliable Garrett technology. The turbocharger assembly is mounted to a prototype equal-length stainless steel exhaust manifold and 3-inch diameter downpipe. The product is 26.1 psi of boost at 4,100 rpm when complemented with an air intake system that is comprised of a carbon-fiber cold air box and 80mm Kevlar-reinforced silicone intake pipe, as well as the AVO Power Air Intake system for charged air delivery. The latter also includes a bar and plate style front-mount intercooler.
Although AVO has developed other noteworthy engine components for this wide-body track-bound demo car, they also sourced some of the best high-performance drivetrain, suspension and brake components in the business. The Exedy carbon clutch kit for the STi is one such technologically advanced component. The carbon-steel multi-plate clutch is a lightweight upgrade from the conventional metallic clutch, which does not have the heat-dissipating characteristics that carbon materials possess after being baked at 3,600 degrees F. The outcome is reduced clutch slippage and quicker, more consistent engine-to-transmission coupling.
In an effort to fully exhaust the issue over friction and traction, AVO modified the STi clutch pack Type-R180 rear limited-slip differential to increase the breakaway setting from the factory adjusted 45 lb-ft with the use of shims. This alteration is normally very delicate since the only way to find out the results is to reassemble the entire differential. A relatively minor change in shim thickness can increase the breakaway setting beyond 150 lb-ft, a situation that would cause the differential to behave more like a locked one than one designed to slip. This would probably be acceptable in a rally car that spends ample time traveling sideways, but would give a track car a serious case of understeer and probably cause overheating in the differential. Of course, done right, the higher breakaway setting would increase grip by maximizing the time that torque is delivered to both rear wheels, before allowing the two output shafts to spin at different speeds.
Speaking of friction, Disc Brakes Australia is a household name for demanding applications and as such supplied the two-piece 5000 series enhanced-performance slotted front rotors and the 4000 series solid slotted rears. The obvious advantage of this setup is improved heat dissipation and reduced stopping distance but the thermographic paint markings that aid in heat monitoring are also notable features. These rotors are fully compatible with the STi brake system, which is comprised of Brembo four-piston fixed calipers in the front and two-piston fixed calipers in the rear.
Since no race car preparation is complete without attention to handling and the mechanical grip offered by a properly tuned suspension, AVO partnered with Original Box, a racing suspension specialty company based in Atsugi, Japan. The result is an uncompromising suspension, one with a fully adjustable coilover system featuring custom shock valving designed specifically for time attacks. AVO adjustable 21mm solid front and 22mm rear stabilizer bars with polyurethane bushings keep the suspension tight.
With a body made for seduction, a heart to excite and a soul to burn, the performance engineered AVO Subaru Impreza WRX STi is within reach even though it seems like a dream.