It’s not a great combination. Vintage 1960 headlights with even older eyeballs; it can make night driving a challenge. With that thought in mind, we opted to upgrade to halogen headlights during the refurbishing of our ’60 Corvette. During the installation of the halogen lights we used a relay to supply power as the original light switch, or in our case, the reproduction light switch from Corvette Central, was not designed to carry the extra load of these high-performance lights. The lights themselves are Hella units (PN 14464) sourced through Summit Racing. We like the additional candlepower, and the flat face of the lights are very cool looking.
We installed the lights in our brand-new headlight housings from Corvette Central, so all the adjuster screws and springs were brand-new too. If you are using the original buckets be sure to check the adjuster screws and the springs that hold the sealed beam cups in place. Replacement parts are available to refurbish your originals.
With the buckets bolted into the fenders we installed the new Hella halogen lights and did a very quick “eyeball” adjustment, based on how the lights filled the chrome 1960 headlight bezels. Months later the car was finally finished and we went through the usual shakedown period after a complete frame-off build. We had things pretty well sorted before we took our first night test drive. It became glaringly apparent (pun intended) that our headlights were in dire need of adjustment. The passenger-side headlights were scanning roadside ditches for raccoons while the driver-side headlights were aimed high enough to earn a “high sign” from oncoming drivers. And so it was time for a headlight adjustment.
Now, some folks like to pull up against a wall and crank things around until the lights are “okay.” We prefer to have them at factory specifications and to that end we set about doing a professional headlight adjustment in our home shop. The job is simple enough, but like any old car project, the more attention to detail the better your end result. Actually, the adjustment takes about 10 minutes; the prep time takes a bit longer.
First, you will need a level driveway or garage floor long enough that the face of your headlights are 20 feet from a flat, vertical surface such as a wall or garage door. We used our shop floor and the garage door, but will refer to it as the wall. You may discover finding a truly level floor or road surface is more difficult than you think.
Check to be certain all air pressures are correct in your tires and that you have about a half tank of fuel. Some people even make final adjustments with a person in the driver seat. We adjusted our headlights sans driver since we have firm suspension. Now, measure from the floor to the center of the headlights and write this number down. If your floor is perfectly level make a horizontal tape line on the wall at this height, ours was 24 3/4 inches.
Next, roll the car very close to the wall. Measure from the face of the headlight to the wall on both sides of the car to ensure the car is perfectly square to the wall. Now, using a straightedge, transfer the center location of the car to the wall, marking the location with a vertical piece of masking tape. Then, turn on the headlights and mark the center of the “hot spot” on the wall with a piece of vertical tape.
All of these lines would be accurate if the surface the car is rolling on is perfectly level. Our shop floor has a two-degree slope built in to allow water to run toward the door. Now, that is “close to level” but you know what they say about “close,” “it’s only good for horseshoes and hand grenades.” If you want a laser-accurate headlight focus we found an easy method to correct the slightly sloping floor issue.
We measured from the wall back precisely 20 feet and laid down a masking tape line on the floor. Since the tape was measured exactly in four locations we know our tape lines are perfectly parallel to the wall. Next, we rolled the car to the tape lines on the floor, rolling it up the two-degree floor, effectively rolling it uphill. We took great care to be certain the face of the headlights were also perfectly parallel with the wall.
Using our center of the headlight height number, we used a small ladder and some shims as a platform for a self-leveling laser level. First we turned the level on the headlights to be certain the beam was in the center of the lights. Satisfied that was correct, we turned the laser around and shot the light beam onto the garage wall. Sure enough, the two-degree slope would have focused our headlights approximately 1 3/4 inches too low. The perfectly level laser beam was used as a guide as we moved the masking tape line on the door using the top of the tape as our “center line.” Next, we measured down and put a 1-inch tape line and a 2-inch tape line below the centerline. These lines would be used for our horizontal adjustment.
Next, we carefully rolled the car forward getting it very close to the wall. When the headlights are very close to the wall the light is cast as a round “hot spot.” We marked the center of the hot spot with a vertical piece of masking tape, doing the low beam hot spots on both sides of the car. Next, using the front emblem as a center guide we transferred the center of the car to the wall and once again marked it with a vertical piece of masking tape.
We now have our crosshair target for aiming the headlights. We very carefully rolled the car back to our 20-foot line. If you do this with the headlights on you will notice the further back you go, the more the light beams drift off target. Once we were at the 20-foot line we measured and noticed we were no longer parallel to the wall, as the car had drifted almost an inch. We rolled the car back and then forward until it was perfectly parallel.
To check our location we used the same ladder and shims for our laser. Since our laser shoots both a vertical and horizontal line at the same time, we carefully aligned the laser with the center emblem of the car. Aligning the laser involved triangulated measurements from the headlight bezel screw on each side to the center of the laser. When the laser was turned on we were about a 3/4-inch off center. We used the laser beam, a straightedge and a Sharpie to make accurate vertical marks on our tape for the new centerline. Certain that we had the correct centerline, we measured from the center line to the center of the high-beam (inboard) light and marked a vertical line here. Then we checked our center to center distance between the high beam and low beam centerlines and made new vertical marks. Everything measured perfectly, so we could now adjust the headlights.
After removing the bezels you will find two Phillips head adjusting screws for each light. We simply turned the screws in or out to move the headlight onto the crosshairs, then down to our previously marked 2-inch line and slightly inboard of the vertical lines. We focused one side at a time, blocking the opposite headlight with a shop stool and a large towel. The actual adjusting was done quite quickly and it was obvious the new lights were going to provide ample lighting.
We took the Corvette out for a night drive and sure enough, the road ahead was well lit and we were no longer blinding oncoming traffic. We may have been a bit maniacal about the prep work and measuring, but it paid off in the end. Vette
Photos by Gerry Burger