Speedtech Performance built this 1969 Pontiac GTO for Tony Madonia at their company in St. George, Utah. The car is powered by a supercharged 416 ci LS3 V8 built by Sullivan Performance. It features Callies crankshaft and connecting rods, Wiseco pistons, Trick Flow heads and valves, Comp camshaft, Speedtech headers, 85 lb injectors, and Whipple supercharger. Brian Macy at The EFI Store tuned the V8 on a Holley Dominator ECU into making 860 hp on 12 psi of boost. Behind the motor sits a Rossler 4L80E four-speed automatic transmission with a Yank Performance 2800 stall converter. A Mark Williams aluminum driveshaft sends power to a Ford 9-inch rear end with a Truetrac diff and 3.73 gears. The GTO rides on a Speedtech ExtReme chassis with power steering rack, Viking Crusader shocks, and Baer Pro+ 14-inch brakes front and rear.
Source: Speedtech
Wait so is the back seat now useless?