How many degrees are we talking about?

 

degrees of timing or degrees of temperature?

Your only asking part of a question.

 

Humor me lol, both.

 

It really depends on the load. If there is alot of heat soaking going on it will make the situation much worse.

It can easily add 5 degrees F into the charge.

This won't affect your timing advance much but at higher RPM I can see a 1-2 degree difference is likely possible.

I would like to actually try a study to measure this.

Look at the maps below, you can see the limp mode programmed in with high IAT.

 

Proof? Just run a scangauge. With my K&N the intake temps would rise higher and quicker than the stock box. The hot air doesn't disappear just because you are moving. You still have hot air coming in from the radiator and getting even hotter when going around the engine. Again. I will never run an exposed element on any vehicle I own ever again unless I had 0 room like on some turbo applications. The intercooler will take care of most of that intake temp anyway.