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Hatch & Sons Mercedes-Benz 280SLR 3.5

"The SL that enthusiasts wish Mercedes-Benz put into production!"

Building these cars was a hot-rodders dream! Imagine being able to go to the parts bin and get absolutely every part you would need to build a hot Mercedes-Benz roadster. One stop shopping! That was the Mercedes-Benz factory in 1969. I'm just an old 1960's hot rodder at heart, but my restoration background made me serious about using period correct parts. Except for the motormount support arms, every part in both models was available from the factory in 1969. I have been building these cars in my head for over 25 years. My problem was combining the high performance SLR vision I initially had, as well as having a fast and comfortable GT car; so eventually I just decided to build both. This is the SLR version.

Hatch & Sons 280SL 3.5 GT - Manual Transmission Euro Spec
  • No Power Steering
  • 3.5 Coupe 11-Inch Vented 4-Wheel Power Disc Brakes
  • No Radio
  • No bumperettes, side marker lights, antenna, etc.
  • 10-1 compression ratio, ported & polished heads, extrusion honed manifolds, 6.3 diameter stainless steel exhaust system
  • European halogen headlights
  • Larger Factory Mercedes Front Sway Bar
  • 15 x 7 Inch Light Alloy Wheels
  • Weighs just 2,950 lbs - 750 lbs lighter than the 111 3.5 Coupe donor car

Except for the motormount support arms, every part in both cars was available from the Mercedes-Benz factory in 1969. We found that fact extraordinary and it tells us that the factory had the capacity to do what we eventually did ourselves. Since we know that they did install a big and heavy 6.3 Litre engine which simply didn't work in the small car, I can't believe that there wasn't some serious discussion about using the drivetrain from the 3.5 Coupe. It is rumored that factory engineers in the sixties secretly built a prototype 3.5 Litre 280SL to show management. The legend also said that management later ordered it destroyed. The 3.5 V-8 engine is only 28 pounds heavier than the straight six and the extra 50 horsepower sitting farther back and lower in the chassis transforms the 280SL into a completely different car.

The key to making the transplant of any drive train work effectively is the proper positioning of the engine. Once we had that determined, we designed motormount support arms and had them CNC'd out of 60-61-billet aluminum alloy. We wanted to have the quality of these be consistent with the remainder of the car. We also designed an engine wiring harness in the original style to integrate the 3.5 driveline to the 280SL chassis.

In 1955, when Mercedes won the Mille Miglia with Moss and Jenkinson, the 300 SLR was a heavily modified version of their 300SL race car with two extra cylinders tacked on to the straight six. None-the less the six cylinder version was no slouch and driven by John Fitch finished 5th overall and 1st in class. At the beginning of this project, we saw the similarity to what we were doing with out "street racer" 280SL. We decided, more in fun than anything else, to call it a 280SLR. And the name stuck.

The SLR version has the much cleaner European look with no Side Markers, Bumperettes or Antenna. It also has an extremely rare 3.5 Coupe 4-Speed Manual Transmission, Manual Steering, European Halogen Headlights, 15 x 7 Alloy Wheels, and Radio Delete Dash Plate. With its 10-1 Compression ratio, Ported and Polished heads, Extrusion Honed Manifolds, and 6.3 Exhaust this is an exciting car to drive even by todays standards. In 1969 it would have been in a class all by itself. What a shame Mercedes decided not to produce at least a limited edition of this car!

Although neither of these cars are presently offered for sale and even with the limited exposure they have had, both the SLR and the GT have aroused considerable interest. Once we have determined that there is a market, we will seriously consider producing for that market. Knowledgeable enthusiasts and 280 owners have told us that these are the cars they wish the Mercedes factory had built in the first place. Maybe it's not too late!

We are also thinking of making kits available for anyone who might be interested in doing this conversion! Please contact us if you have an interest and want to talk about it.

406 Main Street, Hudson, Massachusetts 01749 | p: 978.562.3699 | e:

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