how often do you need oil quarts/changes with vtec ??

i have noticed significant amounts of oil being used up by my car ... especially with the new setup and me being in vtec alot more .... is this normal or should i get her looked at ?? i mean she runs great !! but sometimes i can feel a lag so to speak , or hesitation right before vtec opens up , then i check the oil and its damn near empty ... after a fill up she is back to normal ...

I've never had problem with oil usage in my gs-r and it has 160,000 miles on it. I fill it up at each oil change and when I go to change it 3000 miles later its still right where I want it to be.

how much oil are we talking. Is it like a quart every time you fill up? Has the car ever overheated? Has there ever been a new head put on the old block?