M110 Engine Identification in my '74 w114 Sedan

[Ten13]

Hi there -

I have a 1974 280 Sedan (w114), and the engine, which I believe to be original to the car, carries the following number: 110.921.12.028948. From what I have read, this is a 158-hp @ 5500rpm engine.

This car has a Solex 4a1 carburetor, and according to some research, there was also a 'lower-compression' version, rated at 143-hp (110.931.xx) installed in US-spec cars(?). I also don't see the red, painted-on "USA" letters on the right side of the head, as I have seen on other m114 cars.

My 280 was brought to California in '74 via the MBZ European Delivery Program by its original owners. It has crank windows and column-shift, which I also find a bit unusual.

The question: Is this the normal engine one would find in a USA / California w114 280 Sedan for 1974? I thought these all shipped to the USA with the lower-compression 931.12 mill.

Thanks in advance!

[kraakevik]

The green plate denotes this as a California-spec M110 engine with 8-1 compression rated at 120 bhp.



Tim Kraakevik
kraakevik@voyager.net

[Ten13]

Thanks for the info re: the green CA compliance plate. What is confusing to me is that the engine itself is inconsistent with its 921.12.xx, instead of 931.12.xx stamping. What I have read is that .931 is the lower-compression version of .921 - is this information not correct? Or, is there a third option, that being California cars had the .921 block and a different head?

[Frank Reiner]

M110.921 = USA spec 8:1
M110.931 = Euro spec 8:1

[cth350]

In the fine print on the side of the head, below the cam box, should be the casting number and an "E x.x". Those numbers are the compression ratio expected from the head.

-CTH

[Frank Reiner]

Originally Posted by cth350

In the fine print on the side of the head, below the cam box, should be the casting number and an "E x.x". Those numbers are the compression ratio expected from the head.

-CTH

Front side? Back side? Top side? Bottom side? Right side? Left side?

[Ten13]

Originally Posted by cth350

In the fine print on the side of the head, below the cam box, should be the casting number and an "E x.x". Those numbers are the compression ratio expected from the head.

-CTH

Hey there - I finally had a moment to find the number on the cylinder head. It is:
R 110.016.05.01

A search on The Google hasn't revealed much of anything, hoping someone here might know how to decode.

Thanks in advance!
-greg

[Mike D]

The differences in performance/power ratings are due to piston and cam variations. The cylinder heads are the same.

The casting numbers don't mean squat. They are factory identifiers. The only difference in the molded numbers would be whether it is for a fuel injected or carburetor engine.

[Ten13]

Interesting - thank you for that. For me, this still comes back to conflicting information on what engine/head combo my car may have. It's far more spritely on the road than my '78 280ce, with a 8.5+/- second 0-60 time, a few seconds short of what this automatic-equipped, carbureted sedan should be capable of.

[Mike D]

Different differential gear ratios. Probably a 3.92 in the W115 and a 3.58 in the W123. Apx 9% difference in final drive output. It would definitely be noticeable.

https://www.benzworld.org/forums/w123-e-ce-d-cd-td/1611616-rear-differential-interchange.html

" Years, Model, Engine, Differential Ratio, Differential Case Size, Ring Gear Size

R107
1st Generation mounting
1972-1980, 350 SL/SLC, M116, 3.46, 1.1 Liter, 185mm
1973-1980, 450 SL/SLC, M117, 2.65 / 3.06, 1.3 Liter, 210mm
1981-1985, 380 SL, M116, 2.47, 1.3 Liter, 210mm
1981-1982, 380SLC, M116, 2.47, 1.3 Liter , 210mm

W114
1968-1976, 230, M180, 3.69 / 3.92, 1.1 Liter, 185mm
1968-1972, 250, M114, 3.69 / 3.92, 1.1 Liter, 185mm
1972-1976, 250, M130, 3.69 / 3.92, 1.1 Liter, 185mm
1969-1976, 250C/CE, M130, 3.69 / 3.92, 1.1 Liter, 185mm
1972-1976, 280/E, M110, 3.69 / 3.92, 1.1 Liter, 185mm
1972-1976, 280C/CE, M110, 3.69 / 3.92, 1.1 Liter, 185mm

W115
1968–1976, 200, M121, 3.92 / 4.08, 1.1 Liter, 185mm
1968–1976, 200D, OM615, 3.92, 1.1 Liter, 185mm
1968–1973, 220, M115, 3.92 / 4.08, 1.1 Liter, 185mm
1968–1976, 220D, OM615.941, 3.92, 1.1 Liter, 185mm
1973–1976, 230.4, M115, 3.69, 1.1 Liter, 185mm
1973–1976, 240D, OM616.916, 3.69, 1.1 Liter, 185mm
1974–1976, 240D 3.0/300D, OM617.910, 3.46, 1.1 Liter, 185mm

W116
1973–1980, 280S, M110, 3.69, 1.1 Liter, 185mm
1973–1980, 280SE, M110, 3.69, 1.1 Liter, 185mm
1974–1980, 280SEL, M110, 3.69, 1.1 Liter, 185mm
1973–1980, 350SE, M116, 3.46, 1.1 Liter, 185mm
1973–1980, 350SEL, M116, 3.46, 1.1 Liter, 185mm
1973–1980, 450SE, M117, 3.06 / 3.07, 1.3 Liter, 210mm
1973–1980, 450SEL, M117, 2.65 / 3.06 / 3.07, 1.3 Liter, 210mm
1975–1980, 450SEL 6.9, M100, 2.65 LSD, 1.3 Liter, 210mm
1978–1980, 300SD, OM617.950, 3.07, 1.1 Liter, 185mm

W123
1977–1978, 230, M115, 3.69, 1.1 Liter, 185mm
1977–1983, 240D, OM616.912, 3.69, 1.1 Liter, 185mm
1977–1981, 280E, M110, 3.58, 1.1 Liter, 185mm
1978–1981, 280CE, M110, 3.58, 1.1 Liter, 185mm
1977–1981, 300D, OM617.912, 3.46, 1.1 Liter, 185mm
1978–1981, 300CD, OM617.912, 3.46, 1.1 Liter, 185mm
1979–1980, 300TD, OM617.912, 3.46, 1.1 Liter, 185mm
1981-1984, 300TD, OM617.952, 3.07, 1.1 Liter, 185mm
1982-1984, 300D, OM617.952, 3.07, 1.1 Liter, 185mm
1982–1984, 300CD, OM617.952, 3.07, 1.1 Liter, 185mm
1985, 300TD, OM617.952, 2.88, 1.1 Liter, 185mm
1985, 300D, OM617.952, 2.88, 1.1 Liter, 185mm
1985, 300CD, OM617.952, 2.88, 1.1 Liter, 185mm
Euro Spec
1981-1985, 300TD, OM617.912, 3.46, 1.1 Liter, 185mm
1982-1985, 300D, OM617.912, 3.46, 1.1 Liter, 185mm
1982–1985, 300CD, OM617.912, 3.46, 1.1 Liter, 185mm
1978–1985, 240TD, OM616.912, 3.69, 1.1 Liter, 185mm
1978–1985, 280TE, M110, 3.58, 1.1 Liter, 185mm

W126
1st Generation
1981-1984, 300 SD, OM617.951 3.0L I5, 3.07, 1.1 Liter, 185mm
1985, 300 SD, OM617.951 3.0L I5, 2.88, 1.1 Liter, 185mm
1984-1985, 380 SE, M116.963 3.8L V8, 2.47, 1.3 Liter, 210mm
1981-1983, 380 SEL, M116.963 3.8L V8, 2.47, 1.3 Liter, 210mm
1982-1983, 380 SEC, M116.963 3.8L V8, 2.47, 1.3 Liter, 210mm
1984-1985, 500 SE, M117.963 5.0L V8, 2.47, 1.3 Liter, 210mm
1984-1985, 500 SEL, M117.963 5.0L V8, 2.47, 1.3 Liter, 210mm
1984-1985, 500 SEC, M117.963 5.0L V8, 2.47 /(Euro) 2.24 LSD/(Euro) 2.47 LSD, 1.3 Liter, 210mm "