anything and everything without boring out the block basically. it could have everything and still be called 99% stock. an oxymoron at its finest. peoples view of stock are different from other peoples view. in a 'normal' world (note: not a dyno fag queen supra world) stock would mean a car that comes directly from the showroom with NOTHING done to it. the moment you put a single bolt-on to the car...its no longer stock. again, thats a 'normal' world...so take that with a grain of salt.
then you can get into the calculated estimated times that it 'could' run on a 'perfect' day with a 'large woodie'...but thats a different story all together.