It was probably just enough heat to keep the jets from icing up.
The 376 MPG car was made specially for a mileage competition. The car was stripped down to the minimum weight, and the engine was encased in insulating foam. I believe it also had tall gears in the transmission, and the top speed was only like 30 or 35 MPH. It was in no way drivable on a public road.
I really do apologize if someone has already wrote this and I missed it but am I the only one concerned about being able to get out of my own way??? Yes its really great that you are getting +50mpg but what about when you actually need to put your foot down and will experience wide open throttle will your car actually be able to move now that you are sucking in air that is +100 degrees hotter than your vehicle was designed to ever injest through your STOCK intake? Perhaps this is because I was originally tuning my car strictly for performance and now am trying to improve my economy since I don't have the money to fully build my car and turbo it. Yes I understand that you are driving conservatively but when you have so extremely leaned out your car and are going to wait for a quarter mile gap of no cars before you pull out while the person behind you is honking, flashing their lights, and now is going around you.
I don't think most people would tolerate that kind of performance hit. In my (admittedly mild) experiments I've barely been able to detect any difference...sure, it could probably be measured on a dyno or a drag strip, but not enough that it's unsafe to drive. Any vehicle that ends up that slow, started out as one of the slowest vehicles on the road anyway.
I never saw a measurable difference using it, but I'll likely re-attach it in winter. It and some insulation seemed to help with engine warm up. Perhaps I'll do some experiments with the two on that front when I feel like spending more time in the cold.