Through the years, the ’64-72 A-body fameoriginally designed to support passenger car sheetmetal from Chevelles, El Caminos, and wagons has become one of the must-have and best-known platforms around. GM asked nothing more of it than to fetch groceries and haul the family around; it was never meant to handle the serious demands of autocrossing with substantial rubber underneath. It has quickly developed into one of the most popular foundations for performance. While the aftermarket is fat with new bolt-on components for aging A-body frames, Art Morrison Enterprises (AME) has been evolving and looking ahead; completely redesigning GM’s most popular midsize sedan frame from the ground up.
Twisting and flexing are inevitable in high-grip situations, and bolt-on suspension components can only take the factory A-body frame so far before it has reached the limit for structural rigidity and adhesion to the road. It’s not just the additional load created by hard cornering, either. Combine the stresses of a torque-happy mill and the burden the frame is already enduring is intensified. The factory frame was never meant for overexertion, and it’s prone to cracking, thanks to sharp-angle bends and lack of any lateral bracing. To a certain extent, there’s only so much the factory frame can commit to before that resource becomes exhausted and you lose grip.
Knowing this, AME went back to the drawing board and reverse-engineered a frame to produce a user-friendly bolt-on chassis in a package that all works like a well-tuned orchestra. Their efforts created the GT Sport frame that’s 600 percent stronger than the original open-channel design by boxing it in and forming a latticework of crossmembers. This created a rigid frame and allowed for additional mounting points for suspension components to work off of. Then AME hung an all-new front suspension utilizing tubular upper and lower arms, and a track-proven triangulated four-bar with a 9-plus housing to complete the rear. To fine-tune the performance level and driving style, adjustable antiroll bars (front and rear) with shocks are available as well. The end result was a new chassis that would be stronger than the original, offer a performance ride and handling, and eliminate the need for serious floor modifications.
Whether you’re looking for an ultralow stance or an all-out autocross warrior, AME’s GT Sport A-body chassis can deliver. It includes some of the best engineering to date, and we were lucky enough to get an in-depth look. We’ve detailed the entire chassis and included everything you’ll need to know, including AME’s line of options for suspension components. Look forward to the GT Sport chassis as early as spring 2011!