Though we remember the good old days of Pontiac power and incredible style, many have neglected to set foot in a Pontiac showroom since the big announcement. If, however, you had the foresight to do so in the past couple years, you would have seen a handsome four-door sedan powered by a pushrod V-8 that drives the rear wheels (what year is it again?): the Pontiac G8 GT.
As the last performance car built by Pontiac, it's hard for most of us to believe that it's a four-door sedan. But let's look past that and read the performance numbers. The six-speed automatic and 361-horse L76 rip the car to 60 mph in 5.6 seconds, and this author piloted our G8 GT press car to 13.8 out of the box. The handling characteristics are equally as impressive with 0.87g lateral grip and 60-0 braking in 111 feet (Motor Trend, Aug. '08). These numbers are respectable no matter how you look at them. Since you now know how great it performs, we can once again bring up the fact that this car has four doors and a large trunk. Wow!
Target Audience
Any family man looking for some fun in his daily commuter need look no further than the G8 GT. That's the mindset of Chris Evanco, a 40-year-old mechanical engineer and father of two, when considering the purchase of this '09 Pacific Slate Blue G8 GT. "I previously owned two '06 Pontiac GTOs, and I was very impressed by the rebranded Holden quality. I particularly enjoyed the drivetrain and the availability of aftermarket parts and accessories to transform them into modern-day hot rods," he recalls. Although completely satisfied with his GTOs, a 495-rwhp 575-lb-ft nitrous car and a 490-rwhp 430-lb-ft head-and-cam car, the new G8 GT with its four doors was more accommodating.
"I was looking for something more utilitarian." The GTO has a small trunk due to U.S. crash standards that forced the fuel tank to occupy some storage space. The new Goats also have one of the most ridiculous electric seats to provide rear seat access. Once back there, full-grown adults are very comfortable, but the ingress and egress are dismal. The G8 fixed many of the shortcomings and then received aggressive, modern styling. Pontiac attempted to sway BMW buyers from the German auto-maker's showrooms but probably appealed more to gearhead fathers like Chris.
Since he purchased it from Geri LeBlanc Pontiac in Phibodaux, Lousianna, in October 2008, he has completely transformed it from a tame daily-driver grocery-getter into a tame daily-driver grocery-getter with 572 rwhp.
 The all-new MagnussonTVS-1900...  The all-new MagnussonTVS-1900 kits for the G8 are OEM in appearance and push a lot of extra air into the L76. A set of CNC-ported TEA LS3 heads also contribute to its massive air-ingestion capabilities. |  Complete Custom Wheel set...  Complete Custom Wheel set Chris up with these SP500 wheels. They are 19x9 up front and 19x10.5 out back with 6.6-inch and 7.7-inch backspacing, respectively. |  A Kooks 4-inch axle-back system...  A Kooks 4-inch axle-back system alerts his children that Dad is coming to pick them up from school. |
The Buildup
The off-the-showroom-floor performance of the G8 GT put a smile on Chris' face. The sedate, smooth ride and the Gen-IV LS beast that lurked underneath its hood immediately impressed him. The L76 that powers the GT shares a lot of its common architecture with his LS2, but it also has Displacement On Demand (DOD), which deactivates cylinders while cruising to increase fuel economy. This feature allows the fullsize V-8-powered sedan to achieve 25 mpg on the highway. Chris wasn't terribly concerned with this feature. When he decided to modify it for more power, he knew it was in his best interest to convert the car to a standard LS hydraulic-roller lifter and camshaft, and eliminate the DOD.
He took the Pontiac to Futral Motorsports in Walker, Louisiana, where the technicians tore into the high-tech mill. The factory L92 heads were replaced with highly reworked Total Engine Airflow heads. Stock L92 heads were flow bench-tested to 329-cfm intake and 215-cfm exhaust at 0.600-inch lift. After Tallmadge, Ohio-based TEA ran its CNC program through the LS3 head: It flows 353-cfm intake and 260-cfm exhaust. That's a 24/45-cfm increase, respectively. (LS3 heads are the same casting number, but utilize lighter valves and better springs.) When tested beyond 0.600 lift, the L92 heads drop off to 310 cfm while the TEA heads flow even better at 367 cfm.