GReddy EVO and WRX Turbo Upgrade Kits: Factory turbocharged vehicles like the EVO and WRX have enormous power potential but fall short when matched with their OEM turbochargers. Big gains can be found by upgrading the exhaust, intake, blow-off valve and intercooler and adding more fuel and boost, but by replacing the stock turbocharger with a properly sized GReddy turbo upgrade kit, owners can experience new levels of power. Kits are available for the EVO VII-IX as well as the '02 and up WRX with kits ranging from mild to race-ready. Depending on application, kits either bolt onto factory manifolds with internal wastegates or use handmade SUS manifolds and external wastegates. EVO systems feature either TD06S 20G, T67 25G or fairly large TD06SH 25G turbochargers. WRX owners can choose from GReddy's T518Z, TD06S 20G, T67 25G or TD06SH 25G. Kits include stainless steel tubular manifolds when applicable, Airinx filters, GReddy external wastegates and all hardware, plumbing and fittings needed for a professional installation. www.greddy.com

GReddy EVO and WRX Turbo Upgrade Kits: Factory turbocharged vehicles like the EVO and WRX have enormous power potential but fall short when matched with their OEM turbochargers. Big gains can be found by upgrading the exhaust, intake, blow-off valve and intercooler and adding more fuel and boost, but by replacing the stock turbocharger with a properly sized GReddy turbo upgrade kit, owners can experience new levels of power. Kits are available for the EVO VII-IX as well as the '02 and up WRX with kits ranging from mild to race-ready. Depending on application, kits either bolt onto factory manifolds with internal wastegates or use handmade SUS manifolds and external wastegates. EVO systems feature either TD06S 20G, T67 25G or fairly large TD06SH 25G turbochargers. WRX owners can choose from GReddy's T518Z, TD06S 20G, T67 25G or TD06SH 25G. Kits include stainless steel tubular manifolds when applicable, Airinx filters, GReddy external wastegates and all hardware, plumbing and fittings needed for a professional installation. www.greddy.com

GReddy e-Manage Ultimate: GReddy's e-Manage Ultimate is as close to an expensive stand-alone engine management system you can get but without the price. The Ultimate works with the OEM ECU and sensors and can alter factory settings without tuning from scratch. The Ulimate is application specific and includes the EVO IV-IX. The system controls fuel and ignition parameters and features data logging, map tracing and sensor monitoring for quick and easy tuning. In addition to standard e-Manage airflow-based adjustments, the Ultimate includes new features like parameter set up and map control. An externally mounted toggle switch allows users to switch between preset maps. Maps for individual cylinder adjustment for both fuel and ignition are included and an airflow output map option allows for airflow meter elimination. The unit can also self-tune when accompanied with a wideband air/fuel meter. There are also built-in boost, rev and speed limiter-cut features and various fine-tuning correction maps to adjust for throttle acceleration, vehicle speed, water temp, intake temp, idle and more. www.greddy.com

HKS WRX GT Sport Turbo Upgrade: HKS offers its off-road use, bolt-on, GT-RS kit for the '02 and up WRX. The kit features the same straight-through downpipe, up-pipe and Super Mega Flow Intake as previous kits, but the GT2540R turbo has been replaced with the GT-RS and the split housing extension is now manufactured from polished SUS304 stainless steel. The ball bearing GT-RS turbo's outstanding power potential and responsiveness is an excellent match to the WRX's flat-four, boxer engine design. This GT Sport Turbo Upgrade combined with an HKS Hi-Power exhaust, EVC, F-Con S and larger injectors produced 246.3 whp and 203.6 lb-ft of torque, according to HKS. These figures were achieved with boost pressure set to 1.0 bar. The kit requires the use of an HKS SSQV blow-off valve kit, sold separately. www.hksusa.com

HKS EVO, WRX and STi Intercooler Kits: HKS intercoolers can improve the efficiency and power on the EVO VIII-IX, '02 and up WRX and '04 and up STi by rapidly reducing compressed intake air charge temperatures. The tube and fin design dissipates heat without creating boost pressure losses or lag. As pressurized air is channeled through the core's internals, cool air rushes through the front where the tubes' external radiating fins draw heat out. This decreases the likelihood of detonation and maximizes power output by increased air charge density. Boost response and airflow are also improved due to the larger flow capacity and cooling efficiency. HKS' EVO R-Type intercooler kit features a 600x302x97mm core matched with polished aluminum piping and end tanks. The WRX and STi S-Type intercooler kits feature 600x244x65mm cores, also with polished piping and end tanks, and include Super Mega Flow intake assemblies. All necessary silicone hoses, brackets, hardware and fittings are included for a bolt-on installation. Subaru kits require the addition of HKS SSQV blow-off valve kits. www.hksusa.com

Injen EVO Intake and Intercooler Piping Kit: Injen Technology's SP1898 is a cast-aluminum air intake system complete with intercooler piping. It features Injen's patent pending Mega Ram Technology process that retains factory air/fuel ratios. It can also produce gains of up to 33 hp and 25 lb-ft of torque. Pair it with Injen's larger, more efficient front-mount intercooler (SES1898ICC) and achieve the necessary cooling that your EVO demands. www.injen.com

Injen WRX Intercooler system: Injen Technology's SES1202FMGT allows Subaru owners to replace their miniature top-mount, heat soak-prone intercoolers with a massive track-proven front-mount system. Measuring in at 24x12x3 inches, the Injen front-mount intercooler will support over 800 hp. Best off all, Injen's SES1202FMGT with full intercooler piping will maintain the factory's quick spool-up times Subaru owners have grown to love. www.injen.com

HKS EVO Full Turbo Upgrade: HKS introduces its GT2835/GT3037S Full Turbo Upgrade kits for the EVO VIII and IX. HKS' years of building record-breaking Time Attack and Champion Rally 4G63-powered EVOs led to the development of these upgrades. The HKS GT2835 Full Turbo Upgrade Kit - combined with an R-Type Intercooler Kit and HKS 272-degree intake and exhaust camshafts, Carbon Ti-exhaust, 640cc injectors, Racing Suction intake, EVC, Racing Catalyzer and tuned with an HKS F-Con - produced 330.4 hp and 285.4 lb-ft of torque at a 1.24 bar as measured on an EVO VIII. The GT2835's ball bearing center-cartridge and 0.73 A/R turbine housing allows quick boost buildup for exceptional response, while the 56-trim compressor wheel offers superb power potential for the 4G63 powerplant. Kits include either a GT2835 or GT3037S ball bearing turbocharger, SUS304 stainless steel turbo exhaust manifold, polished SUS304 downpipe, stainless steel Racing Wastegate, polished turbo exhaust manifold heat shield, intercooler piping and are available for systems that are factory intercooled or feature the HKS R-Type Intercooler Kit. www.hksusa.com

Power Enterprise EVO RX6R Setup Pro Turbo Kit: The RX6R kit, designed for the EVO IV-IX, is based off a compact ball bearing turbocharger capable of well over 600 whp. The exhaust and compressor housings can be separately selected and matched per engine specs. The RX6R kit fits EVOs with stock intercoolers by fabricating inlet and intercooler piping. The Setup Kit consists of the RX6R turbo, stainless exhaust manifold, outlet pipe and front pipe, wastegate valve, oil lines, gasket set, installation guide and hardware. Four different sizes of compressors are offered and six types of exhaust housings to make the most suitable turbo unit for your setup. The kit adopts a 76.3mm diameter exhaust front pipe, which is designed to spool the turbine quicker by reducing exhaust backpressure. Another clever feature is returning the exhaust gases out of the wastegate back into the front pipe, instead of releasing such gases directly into the atmosphere. Exhaust manifolds are also heat-treated for durability and strength against cracks. www.powerenterpriseusa.net

Power Enterprise WRX/STi RX6R Setup Pro Turbo Kit: Power Enterprises' WRX and STi turbo kits are rated up to 550 whp depending upon compressor and exhaust housings. Power Enterprise, the largest IHI turbo distributor in the world, offers the RX6R kit for both the EJ20 and EJ25 engine applications. Kits include the RX6R turbo using an external wastegate system with ball bearing technology to support the turbine shaft in longitudal and axial directions for superior boost response at all rpm ranges. Subaru owners can customize the kit from four different types of compressor housings and six types of exhaust housings to make the most suitable turbo kit for their needs. All kits use a large diameter front exhaust pipe, which is designed to reduce exhaust gas backpressure and reroute spent wastegate fumes back into the system, reducing both noise levels and pollution. The kit consists of RX6R turbine, stainless steel exhaust manifold, front pipe, external wastegate, oil lines, fasteners and gaskets. The kit requires removal of the catalytic converter. www.powerenterpriseusa.net

Spearco WRX/STi Intercooler Upgrade Kit: Spearco's '02 and up WRX and STi intercooler kit features the largest air-to-air top-mount intercooler on the market. Utilizing the factory mounting points, the massive 4.5-inch-thick unit bolts on easily without any modifications to the vehicle. The factory turbo piping and blow-off valve can be bolted on easily with standard hand tools. The massive 1,000cfm intercooler offers a very low pressure drop and extremely low charge temperatures. Dyno results have shown performance improvements of up to 15 hp when compared to the stock intercooler. This kit comes complete with clamps and silicone hoses. Boost pressure can now be increased without the horsepower robbing effects of the extreme charge temperatures normally associated with compressed intake air. www.turboneticsinc.com

Turbonetics WRX/STi Blow-Off Valve Kit: Turbonetics' Raptor blow-off valve/bypass valve kit includes all necessary mounting hardware, silicone hoses and adapter flanges needed to upgrade the Subaru WRX's factory bypass valve. The unique proprietary blow-off/bypass valve design allows boost pressure to be vented into the atmosphere without the need for recirculation. The kit also includes a discharge horn to provide the infamous in-between-shifting sound. The new large valve compared to the stock bypass valve allows the vehicle to be more responsive between shifts, preventing compressor surge. www.turboneticsinc.com