head gasket

how do you change a head gasket on a 1997 cavalier z24? its leaking oil. Also, does this oil leak hurt the performance on the car? I took it to the track the other day with the leak and i was running 15.9s compared to my usual 15.4s. I was dissapointed and wondering how bad this needs to be fixed, thank you.

IF you're leaking oil from the head gasket, you have serious problems. I would get it taken care of immediately, as motor grenadage is next. You will start losing compression, and if the coolant and oil are mixing, that's BAD.