Has no one ever built a small block to your specs before ? Certainly cooling one of these motors has been done many times before...I know that a 914 is a small place to put a small block, but wouldnt a set of EGT meters or Air/fuel ratio meter do the same job you are looking for ?

What, other than a lean or rich condition, would cause "hot spots" at one rpm and not another ?

Perhaps a trip to a chassis dyno would let you load the engine while looking for problems with the infrared.

-John

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