Ha, ha,In the good old days of club competition, when we used to have 10 - 15 - up to 20 gt40 club racers, when we had enough cars for a class of our own, every little bit of development intrigue caused concerns over who might be cheating the rules, and this was great for devious people like me to fool the rest. As Doc says, the development of the heat extractor fan box was for the purpose of quick dispersal of rising heat from the engine boiling the fuel in the carbs as soon as we stopped after a fast run, very effective and reduced the risk of fires. However, at arriving on the Isle of Man for week long competition , we transported the cooler box in place on the engine, and there was immediate interest in what it was for . It was quietly intimated that if Porsche could have forced air induction so could we, and we had found a huge power increase and performance !
Almost immediately we were demanded that we could not do that, and at scrutineering an official complaint was raised with the organisers.
This then grew into a major investigation, and the scrutineer wanted to see it in operation. He was very confused how we had achieved positive air induction when the fan was actually extracting air, and with the now screaming hoardes looking over his shoulder were demanding we should banned from the competition . I just left him to it, and in a while he came across to me and ruefully admitted he had twigged what was going on !
We got our scrutineers signature of compliance , and I asked if he had seen the other tricks we had built in ? There was none, but he went back to the car, telling the others watching that there were other possible infringments that must be considered . I have never had a car so closely studied by the other competitors as that day .