As a builder of the esteemed HTR series of fifth-generation Camaro SS's with an upcoming ZL1-based series, Redline Motorsports was eager to be on the forefront of testing the 2012 Camaro ZL1. Owner Howard Tanner was lucky enough to purchase one of the first automatic ZL1s, with a handful of modifications already stock-piled in anticipation at Redline's new Pompano Beach, Florida location. A mere 3-hours' drive from GMHTP headquarters, we were on stand-bye waiting for Howard to take delivery and head to Palm Beach International Raceway for a private test session on April 18th. While a sunny 90-degrees with 1,740-feet of DA wasn't exactly ideal, it was definitely a great test for the sophisticated E67 computer and the ZL1's upgraded intercooler system. Prior to the test session, Redline fabricated and dyno tested a cold air intake before returning back to stock as well as installed a 160-degree thermostat, removed the washer tank (for the intake fabrication), and installed a line lock for easier burnouts. All else was as delivered from GM including the tire pressure.
BaselineRight off the trailer, the ZL1 went 12.39 at 116mph with a sluggish 2.07 sixty-foot with all electronics turned off (such as traction control) in full automatic mode. The manual shifting feature proved too sluggish to utilize effectively, using it resulted in either commanding the shift too early or bouncing off the rev limiter. The sophisticated traction control system (in Race mode), while great for "roll racing," can't recover fast enough to enable a good elapsed time. The (full automatic) Sport shift and Touring suspension mode with traction control off resulted in the best time of the day, a 12.24 at 116mph with a mere 2.03 short-time.
Drag RadialsRedline brought a set of lightweight 18-inch wheels from CCW that were an early prototype fitment. As it turned out, the front wheels just grazed the top of the steering knuckle, which was later trimmed for our next track session. However, the 18x11-inch rear wheels fit beautifully to wedge in the 305/45/18 Mickey Thompson drag radials. These tires were aired down to 16psi and immediately allowed the traction that the ZL1 so desperately needed. The slight increase in tire height slowed it to 115mph, but the added grip enabled a 12.04 with a 1.81 sixty-foot.
Redline Cold Air IntakeMaster fabricator Jay Healy of Redline whipped up a 4-inch diameter aluminum intake with a 6-inch K&N air filter. By removing some of the baffling and silencing characteristics of the stocker, and increasing the diameter, the flow and volume increase would be substantial. The filter would also be grabbing air from the high-pressure area behind the front bumper cover, right next to the brake duct. Given the new location of the MAF and diameter of the tube, this required some modification to the tune. Redline calibrator Howard Tanner made adjustments to the MAF tables to compensate, otherwise leaving the tune (including the timing) alone. On Redline's Land & Sea dyno the results were an unbelievable 46 hp and 33 lb-ft of torque gain, from a baseline of 450hp and 447 lb-ft. Think it's BS? We definitely questioned it as well, but not after the crew swapped the intake over at the track and picked up 3.6mph and dropped .56-seconds. Best time on the day was an 11.68 at 118mph with a 1.73 sixty-foot. The larger intake increased boost by 1psi and even helped lower the rising IATs at speed, though it enhanced a noticeable bog at launch. We'll address this in Part 2 as well as increasing the LSA's overall airflow and efficiency.