A little more on the subject - although from a petrol engine and Jaguar perspective can be read here;

http://www.jagweb.com/aj6eng/technics.php

It's quite a long page - the section on intake temperature is about half way down the page, just after a nice sectioned view of the Jaguar V12 intake tract.


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In response to the statement above that the current air filter set-up is perfectly adequate, I agree entirely, and would not propose any modification or butchery. My herecy is just that I don't buy into the worship of so-called cold air intakes to the exclusion of all other.