As a health care professional, I would also add this to the statement made by racer_tim, where he said, "I don't wear ear plugs and also think the ringing in my ears and head ache after a session could also be adrenalin."

Adrenalin (medically known as epinephrine), is a body's reaction to flight-or-fight situations. All functions needed for fight-or flight of the organism are inhanced (additional nutrition, revamped blood flow to muscles, brain, liver, increased vision, etc)...ergo, hearing by nature's design would not be impared (ringing in the ears hampers hearing).

Drug books don't list tinnitis as being a reaction to epinephrine, either.

I suggest that the tinnitis one has from the race car is a symptom of inner ear damage, caused by loud noise (exhaust), demonstrated by how long it takes to resolve...hours, to days, or forever (as is mine), depending on its severity. Drug induced tinnitis would be gone in minutes (the time it takes for the drug to be metabolized).

Incidentally, the headache is potentially from carbon monoxide, so one might also check for openings in the body.

I hope this makes one think of ear plugs for our tender inner ears.

Bill