Yesterday i changed my oil along with the oil filter and it took 6 quarts. It just a little bit above the full line (close enough to it). I thought they only take 5 quarts? or was this because i changed the oil filter 2?
an EFI 302 does take 5 quarts. The dipsticks were sometimes mismarked at the factory, but usually they would read full after 4- 4.5 quarts. Something is wrong.
Put 5 in it after a hot oil change/complete drain/new filter. After bringing it up to normal operating temperature, pull the dipstick and remark a new "full" mark with a file. The dipsticks in the cars are notorious for being inaccurate --- fill it with 5 qts. and remark the dipstick; don't rely on the factory marks to be correct.
I dont have real experience with it, but I would not run one quart over (it might be fine - I dont know how much one can go over before the crank starts whipping it up). If you drop the front drain, you should drain out 0.5 -1 quart.
too much oil in the crancase will cause windage, which aerates(adds air to) the oil, and causes it to foam. this will cause air to be pumped throught the system and a volume lose without an indication especially at higher rpms. it could be detrimental.