The venerable Opel "cam in head" (c.i.h.) engine, was first introduced in the 1960s as a work horse engine for farmer's cars and taxis, but it evolved over the following two decades to become a very solid and reliable performance engine, especially for rallying.
Ray Baugh asked me recently if I had an old c.i.h. cylinder head that could be used as the basis for an unleaded engine conversion and of course I did have just such a cylinder head in my loft. First it was necessary to find out what size of c.i.h. engine this particular cylinder head originally belonged to.
I remember being told that there was a code relating to the number of fins on the front of the casting long ago by UK Manta guru William Blankley, so I settled down with the Opel Factory Manual for the Opel Manta A series to see if I could find out the answer.
After about 15 minutes I found what I was looking for, the number of fins, follows the following pattern:
0 fins = 1.6N engine
1 fin = 2.0S engine
2 fins = 1.9S engine
3 fins = 1.6S engine
The following illustration shows the location of the fins.
As a double check, the capacity is also stamped into the surface near the side inspection cover, however you should note that it is quite a faint marking and on a used engine is likely to be covered under oily dirt.
This illustration shows the location of the capacity markings, please note that it isn't necessary to remove the inspection cover to view them.
Ray Baugh asked me recently if I had an old c.i.h. cylinder head that could be used as the basis for an unleaded engine conversion and of course I did have just such a cylinder head in my loft. First it was necessary to find out what size of c.i.h. engine this particular cylinder head originally belonged to.
I remember being told that there was a code relating to the number of fins on the front of the casting long ago by UK Manta guru William Blankley, so I settled down with the Opel Factory Manual for the Opel Manta A series to see if I could find out the answer.
After about 15 minutes I found what I was looking for, the number of fins, follows the following pattern:
0 fins = 1.6N engine
1 fin = 2.0S engine
2 fins = 1.9S engine
3 fins = 1.6S engine
The following illustration shows the location of the fins.
C.I.H. engine capacity code - 2 fins = 1.9s engine |
As a double check, the capacity is also stamped into the surface near the side inspection cover, however you should note that it is quite a faint marking and on a used engine is likely to be covered under oily dirt.
This illustration shows the location of the capacity markings, please note that it isn't necessary to remove the inspection cover to view them.
Capacity markings should be visible once you've cleaned the surface |