On the Straight and Narrow

If at any point in your restoration or buildup, you're interested in upgrading your wheels to something more than stock, you'll have to consider several factors in keeping the wheels under the fenders and from rubbing during a turn. To quote the Bentley Manual when it pertains to the front axle, "A change in any single element in the geometry necessarily leads to change in the whole system." This holds true to most anything you do to the front end, and by narrowing the beam to accommodate larger wheels and wider tires, you've altered the original intent of the design.

Like with anything, there's a good way to do this and there's a bad way. The good way is the hard way, cut the beam in the middle and weld it back together.

The best solution is to drop your beam off at Ron Lummus Racing in Anaheim, Calif., to have it narrowed. A word of warning: Because of the lackluster production standards on currently produced beams from other countries, Lummus only works on German beams and won't have anything to do with those from Brazil or Mexico. "The aftermarket beams are almost always crooked--because of the stamps they use and the way they are made--and if we cut a non-German beam and weld it back together, it's going to be even more crooked."

On the extreme end, it is possible to take up to four inches out of a ball-joint front beam without extensive work on the body so the shock towers will clear. On the converse, you can only narrow a king and link beam approximately two inches before the towers are flat on the fender wells. However, determining how much you'll want to narrow your beam depends on what kind of set up you're after. By providing your goals to Ron Lummus, your beam can be narrowed as much (or as little) as necessary. As well, another feature with the Lummus system are the lowering adjusters that allow an adjustment to the torsion leaves. This small adjustment is exaggerated by the time the angle is transferred to the spindles, allowing for a pre-determined selection of stances. Depending on the angle and position of the adjusters, the front end can be lowered a little or a lot.

We followed Ron and his crew around his shop one afternoon while he took us through the proper process they use to narrow a beam. This example is narrowed by four inches; however, the process is the same regardless of the amount narrowed. This process can be done at home, but we don't really recommend it.