Cold air intake best temperature?

The colder the better. I know guys that run air through ice coolers. Obviously you will be sucking atmospheric temperature air in with your "Cold Air Intake" just like the factory one.

Cold air intakes are a scam. The best intake is the stock intake that came with the car. Put it back on. When a cold air intake fails, it fails open, not good for the engine. When a stock intake fails, it fails closed, no dirty stuff is going to your car's internals.

The colder the better. The colder the air the more dense it is so it contains more oxygen. But it's largely a theoretical exercise because the advantages are minimal.

You vehicle came with a good CAI from the factory. it is just plastic instead of shiny chrome. It also has a convenient paper replaceable air filter. No you have a POS that takes 4 hours to clean properly and the oil on the filter will migrate to the MAF sensor and ruin it.Put the stock set up back on! You won't be noticing any HP or MPG difference.