Mercedes-Benz Tech Letters - Tech Review - European Car Magazine

How Low is Too Low?
Since lowering my 1995 Mercedes C280 with Eibach Pro-Kit springs, I have experienced abnormal tire wear due to excessive camber in both the front and rear. RENNTech supplied elliptical rear bushings, which have corrected the rear camber settings to spec., but I still have too much negative camber in the front (about 1.5 degrees negative). I've installed Mercedes factory camber bolts in the front, but need to take out another .5 to .75 degree of negative camber. I'm running 17-in. AMG Aero II Monoblock wheels with 225/45-17 Bridgestone RE730 tires.

I've searched everywhere, but can't find a company that can provide me with the necessary hardware to correct my problem. Have I lowered the car too much? There must be some solution available.
William Parrish
via the Internet

Most people consider negative camber greater than 2 degrees to be excessive, but your camber is well within the range normally considered acceptable for enthusiastic street driving. The source of your negative camber is the aggressive camber curve designed into the unequal length suspension arms of your Mercedes.

On a stock vehicle, this keeps the contact patch closer to flat as the body rolls during cornering. The mild lowering provided by your choice of springs accentuates this effect, starting the car along the path to negative camber while it is in the static position. This should give your car outstanding cornering grip and even tire wear when driven around corners in the sporting manner advertised by your decreased ride height.

On the other hand, if you mostly cruise on the freeway, you will experience wear on the inner edge of the tires ahead of the outsides. There are two easy solutions: One: Return to the stock ride height; and two: Take your car to the track and work some of that rubber off the outsides.

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How It Was Done
I'm very interested in a list of the improvements made to Kevin Clemens' "Around the World" Mercedes-Benz 220S in preparation for the journey. My father has a 1956 220S that's a truly competent Sunday cruiser, but he is always looking to improve it--currently the brakes, which like many cars of the '50s, are awful compared to modern autos. A major improvement he made to his Mercedes was a switch to '70s-era Mercedes steel wheels w/hubcaps. This switch allowed for 14-in. tubeless radial tires, resulting in much improved ride, handling and safety. The bolt pattern is the same between the stock 13-in. wheel. Any info will be appreciated.
A. Wilken
Via the Internet

Mercedes-Benz has always had a philosophy of introducing change in a very gradual way. When a new body style is introduced, for example, it typically uses the engine and running gear from the previous model. One of the real advantages then in driving an old Mercedes-Benz is that parts from newer models are easy to adapt. I took advantage of this with my Around the World car, a 1959 Mercedes-Benz 220S sedan, and there is no reason you shouldn't be able to do the same on any daily-driven older model to make it safer and more fun.

The first and biggest upgrade, as you have already pointed out, is to change from the lowly 13-in. tires to modern radial tires on 14-in. wheels. Stay with a fairly narrow 70-aspect ratio tire, the improvement is so great it will feel like you are driving a different car. Likewise, the front disc brake setup from a 1963 and later coupe can be grafted onto an older sedan, as long as you replace the whole spindle. I ended up using the stock master cylinder and brake booster, but should have gone with a later dual master cylinder setup for better safety. The only downside to the disc brakes was an increase in the car's turning circle.

Suspension upgrades are also easy to do on these cars, and they benefit from stiffer springs and shocks. I used specially made Eibach springs to gain some ride height--you might want to do the opposite and lower the car a bit. Gas-pressure Bilstein shocks also helped keep the car under better ride control and reduced the tendency to dive under braking.

The electrical system on these old Mercedes-Benz cars is surprisingly durable, and most of the original wiring was used in the car. I did replace the generator with an alternator from a 1985 Nissan pickup truck and had to fabricate brackets to do that. I also had the radiator re-cored to triple thickness and adapted a floor shifter from a 1965 Mercedes-Benz sedan to replace the column shifter on my car. Hella provided me with halogen headlamps that made it easy to see while driving at night, and they would be useful even on a daily driver. I also put some extra taillights in the rear window so that I could be seen from behind while driving through sandstorms in Turkmenistan. I tried to keep as much of the charming wood and leather interior intact as possible but replaced the low-back stock seats with some high-back rally models. Some of the other teams in older Mercedes-Benz cars chose seats from later Mercedes-Benz models and bolted them right in. I also replaced the complicated heating and ventilation system with a simple setup from a hot-rod shop.

All in all, the car I chose was a pretty good starting point for an adventure of this sort. With a few modifications, using almost all Mercedes-Benz parts, I was able to make improvements that helped me and my co-driver go around the world in 80 days.--Kevin Clemens