Pirelli run-flats on stock chrome C5 wheels provide the rolling power, with black powder- coated calipers handling the whoa-power.
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ADVANCED PCM TUNING Because of the larger (60lb.) injectors that are replacing the stock units (26lb.) and other hardware modifications made during the dual turbo installation, the software of the power control module has to be updated to reflect the new parameters these hardware changes have necessitated. These parameters include the injector flow rate, the dead time (the time it actually takes the injector to open after the pulse command) has to be adjusted, the minimum pulse rate. Due to the fact that we’re running with 6psi of boost, the stock parameters of the mass air flow sensor will be adequate as they are. And since the car has its stock cam, it is expected that it will still be very drivable with good emissions. With the additional air flow the boost is providing, the engine timing will also have to be adjusted through the tuning software to retard it due to the additional cylinder pressure. So, in effect, what is being altered are the fuel and spark settings in the tune. A Predator tuner is part of the STS kit; however, the Predator doesn’t work on the older PCMs of the 1997 and 1998 year C5s. For tuning these years, an HP Tuner or EFI Live or an equivalent tuner is required. Rick Squires claims the dual rear mount turbos would not adversely affect mileage, but in fact may actually improve mileage. One would think that putting injectors in that are much larger than stock would give you less miles per gallon, right? But that isn’t the case. The stock injectors require a longer burst to deliver the precise amount of fuel the engine is demanding; the bigger injectors deliver more fuel in a shorter burst, so the mileage doesn’t take a hit. It’s easier to understand if you compare a garden hose to a fire hose. They can both fill up a 5 gallon bucket, but the fire hose will do it much faster; that’s the same effect of the larger injectors with a shorter pulse width. Squires recommends having a boost gauge installed so you can monitor the actual boost being produced. We procured an A-pillar with the gauge platforms built in, and we added AutoMeter boost and fuel pressure gauges. For the custom tuning, the car went to EFX Tuning in Lindenwold, NJ, where head honcho Dave Krysienski handled the injector swap, the HP Tuning and the dyno runs. Here’s the project car strapped down for the dyno runs. The object in front of the car is a high-velocity fan for blowing the exhaust out the door at the rear of the building by evacuating it under the car.