In all production G8s, a basic...
In all production G8s, a basic oil and air strut is standard. The Pedders strut is a nitrogen-charged gas and oil damper. The gas and oil work to provide a more controlled response to road imperfections. Every Pedders strut is pressure-tested before it leaves the assembly line. Typical OE and aftermarket coils are wound to a height tolerance of 15 mm; Pedders' coils are wound to a tolerance of 2 mm. Ride heights are measured on every Pedders coil before they're put into a box for retail sale. The spring rate is 30 percent stiffer than stock.
We also saw that the factory alignment had the left front wheel toed-in and the right front wheel toed-out; the Pedders alignment toed-in both front wheels very slightly. This can be done because the G8's platform is so good that it will drive exceptionally well with minimal toe. These toe values improve turn-in response and tracking through turns.
To complete the alignment, Basica increased rear-wheel negative camber (see G8 Performance Alignment sidebar) to further improve tracking and turning, and still get excellent tire life.
Finally, addressing the issue of tire wear, Basica said, "As the G8's miles accumulate, we're seeing that tire wear is controlled, even with very aggressive alignment settings. This is the direct result of the proper application of GM's billion-dollar VE/ZETA development budget to create a great platform, combined with tuning via Pedders suspension bits."
Testing
With the alignment dialed in to Pedders' specifications, we then traveled to Pasco Community College in Dade City, Florida, to collect data on the G8 at its testing facility. We brought two '08 G8s, a completely stock base sedan, which set our baseline numbers, and the G8 test car, identical to the base car except for the addition of the Pedders components. All testing was performed with a G-Tech RR Performance Meter courtesy of Tesla Electronics (www.gtechpro.com.)
Pedders' eXtreme adjustable...
Pedders' eXtreme adjustable rear sway bar (red) measures 20 mm, compared to the factory 18mm production piece. The recommended setting is one position from firmest to reduce the body lean dramatically while maintaining the neutrality and balance of the car.
Our first run was the 400-foot slalom to test the transient response of the suspension system. Normally we would use 600 feet, but there wasn't enough room to do it safely, nor was there enough room to run a traditional slalom test, where the speed is steady throughout. Instead of entering the slalom at the maximum safe speed, we had to enter accelerating.
The base G8 went first and set an exit speed of 52 mph. Although the cone set at the 100-foot mark was no problem for the car since we were still getting up to speed, excessive body roll took over at the 200- and 300-foot marks. At full throttle, the base sedan couldn't complete the slalom. The test drivers had to back off acceleration from 200 to 400 feet. The second to sixth runs on the slalom showed an improvement of 2-4 mph, however, adjusting tire pressure to 40 psi and then 44 psi showed no noticeable change in performance.
The Pedders suspension made a significant difference on how the G8 handled the cones. Our test vehicle clocked a 58-mph exit speed, 6 mph more than the base sedan on its first run. More importantly, it handled the slalom consistently and safely, exhibiting minimal body roll, and allowed the G8 to maneuver through the test cones at full throttle.
The Pedders Track II suspension...
The Pedders Track II suspension kit is a purpose-designed, matched package. Here we see the front suspension components installed. Pedders says the result is greater than the sum of the individual parts.
Our second test was a 200-foot-diameter skidpad, and the base sedan went first. The goal of the skidpad is to increase the speed steadily to achieve the highest lateral acceleration reading before the tires "break loose," or the car can no longer maintain the same path. The base sedan produced a left/right average of 0.78 g of lateral force and an average test speed of 36 mph.
The Pedderised G8 left/right average was a whopping 0.88 of lateral force and had an average test speed of 39 mph. We repeated the test three times and received consistent results.
"There was significant understeer in the stocker," said Jay Heath, editor of VETTE magazine, who also aided in testing the vehicles. "The Pedders suspension virtually eliminated that trait, although there was still not enough power to induce throttle oversteer for our testing."
Conclusion
According to our data, the Pedders Track II suspension system for the G8 makes the Pontiac faster and more consistent than a base sedan in slalom and skidpad testing. Through the slalom, the Pedderised G8 is 8 percent faster and demonstrates a 13 percent improvement on the skidpad.