"The Confines of the Engine Compartment"

[JeffYoung]

I dislike the radiator being considered a standard part of the outline of the engine compartments due to mid engined cars and oddballs like the 5cyl audis, not to mention 1/2 width radiators found on many hondas and a few other cars.

in the case of the miata - yeah, a fine, common sensical boundary, but I think we should be clear with ourselves that it is not a valid definition in MANY cases.

This is a pretty easy "know it when you see it" thing though. Something like "within the confines of the engine compartment, which is typically bounded by the radiator (front), hood (top), inner fenders (sides) and subframe or other engine mounting points (lower)" -- something like that.