Performance & Hotrod Business - January '15

Issue link:

Contents of this Issue


Page 55 of 118

January 2015 n Performance & Hotrod Business n 53 A modern drivetrain and suspension add new stresses to a frame, and in many situations to areas of the frame that have never been stressed before. (Photo courtesy Art Morrison Enterprises Inc.) Not Your OEM's Chassis OEMs adopted unibody construction in most passenger cars starting in the 1960s. It was a change that was good in some respects, but lacking in others: "OEM chas- sis were designed to be inexpensive and fast to build on an assembly line and get you down the road in a somewhat safe manner with a degree of comfort that suits near anyone," says Foster. "Our hand-built cus- tom chassis gets you down the road with a 'near anyone' comfort level manner too." The difference is that the custom chas- sis also has the ability to "get you down the road in an aggressive driving style manner for those that fit outside the 'near anyone' box," Foster continues. He describes it as having "that straight line acceleration" and being able to "hang with a BMW in the canyon." The drawbacks of unibody construc- tion created a void that others have sought to fill as well. "Our design works with (rather than replacing) the factory rear unibody struc- ture, which produces a much more struc- turally sound vehicle," says Schwartz. "Mustangs and Mopars, for example, benefit greatly from this, as they were extremely weak unibody cars, and their engines, transmissions and rear ends bolted to sheet metal. In our case, they bolt to our chassis, and the body then fastens on top of everything." As with other custom chassis builders, Perry says his is not a "one-size-fits-all," but more engineered to be what the owner of a particular car is looking for. "Ours in particular are much lighter, much more purpose-built," he says. Custom- and aftermarket-built chassis provide other benefits as well, including increased torsional rigidity for more pre- dictable handling and ride, which can be accomplished using boxed or round tubing rather than the open-channel or unibody frames and structures OEMs commonly used, more body mounting locations and more bracing for additional strength. Also, there is an element of flexibility that can be designed into the chassis to fit different budgets and different performance levels for different customers. Street/Track/Strip For some, a street chassis is the same as a race chassis; the difference lies in what's bolted to it. For example, Schwartz says the Schwartz Performance G-Machine chassis is designed for both street and race applica- tions and that "a simple alignment change, coilover spring change to a stiffer rate, and stiffer shock settings is all it takes to change (Photo courtesy Speedtech Performance USA)

Articles in this issue

Links on this page

view archives of THE SHOP - Performance & Hotrod Business - January '15