Concentrating most of his money on the engine rather than external cosmetics, Ben was able to generate his first stage of substantial horsepower. A year after he purchased his chariot the Supra went from making 296 rear-wheel horsepower to laying 365 to the DynoJet roller.
This was achieved by adding boost pressure via a Blitz SBC Dual Solenoid boost controller. Utilizing the Blitz unit not only allows the factory boost levels to be surpassed, the unit also cut turbo lag down to a minimum. The boost controller is a dual solenoid set-up, which means the wastegate's valve doesn't crack open till a few psi before its max boost. This causes the turbo to spool harder in the low to mid rpm levels. Added boost pressure needs extra breathing room and since the factory downpipe and exhaust system can be a horsepower killer Rod Millen replaced the factory downpipe with a Rod Millen unit and a GReddy exhaust system. Since the car was based on retaining the stealth look, Ben found the GReddy Power Extreme exhaust system the most camouflaged to onlookers.
HKS and the Toyota Supra go hand-in-hand when dealing with engine management and two of the most popular units incorporated to the factory ECU are the HKS Vein Pressure Converter (VPC) and Graphic Control Computer (GCC). The VPC grants removal of the OE air flow meter in place of a speed/density-type system while the GCC entitles the user fuel tuning capabilities through designated rpm ranges. The factory ECU received a ROM-tune by G-Force which enhanced fuel delivery as well as timing compensation for the extreme boost levels.
Just when you thought the ponies stopped here, Ben's addiction to horsepower grew like an unchallenged wildfire. This encouraged Ben to return to Rod Millen Motorsports for a full turbo package. The crew immediately replaced the factory turbo set-up with a pair of HKS 2835 GT ball-bearing turbos complete with two standard HKS wastegates, air filters and exhaust manifold. The new set-up relocated the turbos so it was necessary to replumbd the air intake. Since the factory air intake is like eating steak through a straw Ben opted to use Twin Power Flow air filters with aluminum HKS intake pipes. An HKS front-mount intercooler which replaced the factory side-mount greatly increased the cooling capacity of the turbo system. To conceal the intercooler, Ben cut out a metal mesh grille and had it powder-coated black making it difficult to spot the HKS core through the bumper. Once the car was up and running it was back to the dyno for a quick retune of the VPC and GCC. As the car was commencing its second low boost pass of 17 psi the clutch was unable to clamp the flywheel horses to the rear wheels. Although the second pass was unrecorded, the first low-boost pass was able to generate 480 horsepower which was quite promising.
GReddy boost pressure and...
GReddy boost pressure and exhaust temperature gauges are used to relay vital information to the driver. The exhaust temp readout can help determine if an engine is running to rich or lean and the boost gauge signals if the car is over boosted.
The Supra relies on an HKS...
The Supra relies on an HKS twin-turbo set-up complete with front-mount intercooler and racing downpipe. From the outside of the engine it looks like a race-prepped JZA engine but taking apart the engine would reveal it contains all OEM rotating internals. This seems to work for most Supra fanatics pumping over 600 horsepower.
A Blitz Dual Solenoid Boost...
A Blitz Dual Solenoid Boost controller maintains boosting characteristics. This particular boost controller works great for low to mid range spooling. The reaction time on the controller's solenoids react so fast it's able to hold the wastegate's valve shut until just before max boost.