I don't have an easy way to check the temp on my civic VX, but the stock air intake is taking air from a little to the right of the top of the radiator, and then of course the throttle body has what looks like the hot side of the coolent line running thru it, I'm told to prevent it from icing up, the whole intake manifold seems to stay pretty warm.
if you really want warm air intake something to think about might be the warm air intake design that older carburated cars used, they have a little vaccum "motor", and a theromostat valve that sits in the air cleaner houseing, right on top of the carubrator, when the air is cold, the valve closes, and the "motor" opens a flap that lets the engine pull air from a cover that goes around the exaust manifold, it's one of those things that if you buy a carubrated car, and the owner says it has a hard time running in cold weather, look to see if they removed this "useless" piece of ductwork, I've seen countless cars on Ebay discribed as only likeing warm weather, and you can see this duct missing in the photo.
yea, the xb has that composite intake manifold, and i want one!!
i think when the air/fuel mixture gets warmer or colder the motor adjusts the timing and you get different results and if its two warm the timing is thrown too much because of the cr, as previously mention, either way its pretty interesting...
don't waste your time or time will waste you