Finishing Samson the M120 R107 - Page 8 - PeachParts Mercedes-Benz Forum

Roncallo · #1 09-24-2019, 10:10 PM

Many people hear are aware of the M120 powered R107. If not the thread is here:

M120 into 560SL (With Pictures!)

But what has been going on since. They say these projects are never done and yes there is some truth to that.

Once I got the engine installed and successfully running, I kind of took a breather to enjoy the car for a bit. Plus I moved from CT to NC and had to build a new shop. So about 2 years ago I decided to perfect the bread.

While Samson ran strong and reliable and had driven from main to FL and back along with several other long distance excursions, there was still a bit of fit and finishing to do.

The following was still left has been being actively addressed over the past 2 or 3 years.

1) Could I build another one and could I make it fit both an M120 and an M113.

2) Badly needed real LSL differential, done see: Differential Build Tool Ideas.

3) Needed to get the ABS working. Done with the 126 diff installation above.

4) Need to get the speedometer working. Hopefully will be done in about two weeks see: Connect 722.6 Transmission to Electronic Speedometer

5) Need to get the AC working. Just started looking into this.

6) Need to make a windshield washer reservoir. Will be looking into this when I can't work on the AC due to cash flow.

With that complete the car will very well refined with only two minor issues.

7) Evaporation emission system need to be completed.

8) M120 Tandem pump needs to be disassembled to have the extra hydraulic rotor removed. That will allow me to get rid of a reservoir that does nothing but pump fluid around in circles.

9) A cold air intake would be welcome.

10) Make more room for M120 / M113 twin cats, see: Dimensions Needed for After Market Cats

With items 2 thorough 9 complete. The car will be completely disassembled and sent out for paint. While out for paint Samson's modified subframe will be fit into a parts car I have and the M113 engine will be test fit. Any adjustments required will be designed into a new subframe designed to fit both the M120 and the M113. I may at this time also apply modifications to the frame for more cat room. That is a tough one as it requires cutting a main structural beam (the tunnel) of the frame and suitably welding it back together. That will require me to break out the aerospace structures books which have not been cracked for 30 years.

When Samson comes back from paint, the engine and components will be cleaned and reinstalled. Samson will be an M120 powered R107 as if it left the factory that way.

Tooling has already been built to do any machining required on the subframe mods in preparation for project.

First picture shows the subframe holding fixture with a front subframe on the mill. Other pictures show additional parts that were rebuilt or made ready in for the project.

Along with replacing the larger 129 differential with an overhauled 107 diff, the shortened axels from the 129 had to be replaced with stock 107 axles witch are shown ready for shipment to the rebuilder. The shortened drive shaft gets replaced with a rebuilt stock 107 shaft. All that work got me back my limited slip diff and ABS.

The last two pictures show the cutting tool I made and how its installed. It is a cut off wheel on linear bearings. The last picture show how it is attached to the car to make a nice square cut on the lower edge of the tunnel.