Decades ago, there was only one way to “fix” the front suspension on a stock suspension door slammer race car.
It involved cutting, pasting, and tweaking the A-arms to increase caster (which is the tilt of spindle) and at the same, reduce the camber change (as the suspension went through its travel) in the front end.
The stock front suspension components that rolled off Detroit assembly lines through the decades were not (and some are not still) optimized for drag duty or carving corners.
Early cars were built typically with little caster so that Aunt Bessie could park it easily without power steering.
The trade-off is the car being unstable at higher speeds (Aunt Bessie wasn’t going there anyway).
Camber is an issue too: It changes as the front end goes through its travel during a wheel stand.
It doesn’t take a rocket scientist to see how goofy the front wheels look on some cars as they dangle in the air. With some of these combinations, as the car comes down to earth, the drama can unfold rather quickly. Usually, it manifests itself as hairline cracks on stock A-arms (been there, done that and I’m sure more than a few of you have too).
That was then. Today, for many fast “door” cars (race cars and street-strip cars that originated on a factory assembly line), you don’t need to cut and paste the front end components to fix the geometry. You can simply choose a set of aftermarket upper and lower control arms with considerable tricks already built in (obviously, not a NHRA/IHRA legal swap for a Stocker or Super Stocker, but those are another story).
There are plenty of companies offering tubular control arms that bolt right into place. But what should you look for?
Some companies are, for the most part, building road race-style hardware while others are dedicated to drag racing. Some A-arms can work well in both applications.
When it comes to A-arms we’ll show you what to look for in the accompanying captioned photos. In this case, the examples shown are from Detroit Speed, but the picking and choosing process applies to pretty much all examples.
Wayne Scraba is a diehard car guy and regular contributor to OnAllCylinders. He’s owned his own speed shop, built race cars, street rods, and custom motorcycles, and restored muscle cars. He’s authored five how-to books and written over 4,500 tech articles that have appeared in sixty different high performance automotive, motorcycle and aviation magazines worldwide.
There are a number of different manufacturers that offer tubular suspension component upgrades. Naturally each one insists that theirs are better because of an advantage in design. Anything would be better, especially considering the less than optimal OEM components on my’70 Mustang Mach 1 with its original “competition” suspension. Detroit Speed offers some impressive upgrades but a more in-depth article comparing some of the technical aspects of equipment available from different manufacturers would be appreciated.