Ian, it would depend if the Jarama engine is a Jarama "S" engine or not. The normal Jarama engine had a different compressio ratio. The "S" engine was the 365 HP engine vs the early Jarama engine being 350 HP.
The valves, rods and crank will work. The heads will not, as the Countach casting was different. I am sure you most likely could probably make them work though.
The liners would be the same also.
Chadbourn Bolles
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