Hello all and Happy New Year! I've done an internet search and cannot find the info I need so thought I would try here. Many Google results are for this site.

I've recently acquired a 1985 Euro 280CE with the 110.988 engine. I've determined that it has its "born with" engine, (at least the block), but need to decode the head and cams because I have a suspicion that they might have been changed along the way with a top end from another engine.

The information I am looking for is a decoder for the various M100 cylinder heads and cams, specifically which part numbers are correct for my engine. I have access to some parts cars and without this info, I don't know which parts I am looking at. I cannot assume that the parts are original to the cars they are in after 45-50 years and rebuilds, etc.

Does anyone know of such a warlock on the web? Thanks in advance.

Re: Cylinder heads
There are differences in valve stem & guide diameters, and in valve head diameters. There are no external clues for these differences.

Re: Camshafts
There are seven different exhaust cam code #s, two of which were USA 1973/74 only.
There are five inlet cam codes, two were 1973/74 USA only.
The code #s are stamped into the rear face of the camshafts, and relate to the number of journals on the shafts.
Exh.: 24, 57, 71, 78 [20, 95]
In.: 25, 67, 74 [33, 91]

Thanks for this. I have read some older threads you were on and tried to see a code on my exhaust cam using a flashlight and a small mirror but could not see any markings. The rear of intake is of course hidden in the tower when installed.

I have read that Euro cams have a different profile than USA cams, high/low compression engines and should not be mixed and matched. As stated previously, I am not convinced that mine have not been changed and want diehard evidence that the correct ones are installed, I might as well be from Missouri in that regard.

It sounds like having cams installed with the wrong number of journals would not be good. I'm assuming that the numbers in parentheses are the '73/'74 USA ones? Do you know of a table online or do you know which ones are correct or compatible with a late 100.988 Euro motor? Thanks for your time and knowledge.

The available, published data in the MB manuals strongly suggests that the profiles within a group of code #s are the same irrespective of country of delivery. Hence, there are two inlet profiles - '73/74 USA, and all the rest, and similarly, two exhaust profiles. If original, the camshafts in your engine should have five functional journals each. It is possible that shafts were installed of codes that had more than five journals, however they will just be along for the ride.
Pistons were supplied in two crown configurations - standard/normal, and low compression. Engines delivered outside the USA, unless specifically ordered as low compression, will be standard/normal.