Since Jeff is constantly adjusting his tuning, having access to the peak exhaust temperatures and boost levels with real-time control is essential. A custom car PC and full size keyboard interface seamlessly with the CD/DVD/GPS/NAV display in the center of the dash. A second, USB-driven “mini keyboard” rests over the flip-up ashtray cover. The PC is also connected via CanScan to the car itself so any warning lights can be monitored and corrected immediately. Still, life with a turbo rotary isn’t all roses. “The previous engine died a warrior’s death, pulling a grade at 12 PSI while passing a guy in a Mustang who didn’t feel he should be passed! It got a little too hot and I didn’t notice it in time to keep it from detonating. Because of the crappy gas in Phoenix, now I keep it in the 9 PSI range on hot days.” Not only is Jeff completely unafraid to get his hands dirty, he considers an occasionally blown motor to be an acceptable cost for his “fun”.
Handling receives two thumbs way up. The combination of soft (for a lowering spring) rates of the AutoEXE springs and Tokico D-Spec adjustable shocks easily absorbed the worst cracks in the parched desert pavement while providing an aggressive drop. We’ve noted that the RX-8’s suspension likes soft rates and long travel and that accentuates the mechanical grip available from the Nitto tires. Proper choice of shock rates is critical; go too stiff on an RX-8 and you’ll be chasing the tail in the twisties. Never busy, we were able to place the car anywhere we wanted in a turn, at least up to speeds which would have earned stern glances from the local law enforcement. Jeff admits that the staggered eight- and nine-inch wheels aren’t the best for pure handling but “I loved how they look on the car!”
Once the snail spins up, there’s strong power from 3500 RPM to the red-line. A turbo doesn’t change the high-revving, low-torque nature of the RENESIS to that of a V-8 but there is MUCH MORE thrust available than anyone has the right to expect from 1.3 liters. Although his last attempt to dyno the car in Phoenix wasn’t successful due to temperature issues, he reports “I was making more power at 2500 RPM than the typical RX-8 makes peak in stock trim at 8000 RPM”. First and second gears go by in a flash, third and fourth carry you into illegal territory in haste, pressing you back into the seat, fifth and sixth will get you arrested, locked up, and possibly deported. One freeway on-ramp and we were exclaiming, “This is how they should have been shipped from the factory!” Why Mazda has refused to build a boosted Mazdaspeed variant remains a mystery. Perhaps Ford wouldn’t be happy with a Mustang-whipping stable-mate, but we can only imagine what a version like this would do for the RX-8’s slacking sales numbers. Certainly the cost of a few dress-up parts, a turbo system, and tuning is lower than developing a brand-new model, right?
What was truly amazing was that, for our test drive, due to fuel quality and outdoor temperature concerns (it is a desert you know) he’d backed the boost down from his “winter” setting of 12-14 PSI down to an extremely tame 6 PSI! We asked if it’s this much fun now, what’s it like on full boil? “It can be pretty scary.” Jeff replied while chuckling fondly. While we don’t believe a turbocharged rotary will have STI or Evo owners quaking in their shoes in a drag race, it greatly improves the car’s overall tractability and fun quotient. “I turned a 290+ HP dyno run back in Maryland with a smaller turbo and less boost.” At “full power”, Jeff estimates the horsepower climbs to a peak of 320 at the tires. Weighing in around 3100 lbs, without a single piece of aftermarket carbon fiber or titanium, this brings the power-to-weight ratio under 10:1, infringing on BMW M3-like numbers, for a fraction of the cost! Power, handling, and looks? Now that’s the sort of magic we’ll take to the bank!