sounds like dirty fluid. Used to happen all the time in my C6 and once in my 350. Had to pull the clutch pedal back up from behind it. The corvette slave cylinder design allows a tiny bit of dust to enter the fluid and it needs to be flushed out regularly.

First Day ever at a Track Instructors comments on car
 

Sebastien my Instructor drove my car for three or four laps.

He has driven a 370Z before propably was not tuned because he said the car had good power thru the gears. For OEM rotors the brakes were really good, did not fade at all. Looked at rotors after event and were very smooth. He had to make an ajustment to the short shifter and blipping the the motor.
He had said that you have to be right on when you blip the motor or you feel the back wiggle abit and he was right. All in all he complimented me on the car a said it was vey srtong and I did see that as at times I could pull away from a few cars that were on the track, mustang included.

I trust him on his comments as he drives a few different cars. Radical, EVO, Lotus and a GT3 twin turbo. He held the Sebring lap record for a while don't remember which car it was, may have been the radical or the EVO.
he also said that on the clutch problem it was probably an air bubble as someone already suggested.

Talking about all of this is getting me all worked up to try another event autox or track? I quess when it gets in your blood you start to get hooked. I still want to learn and have fun at the same time.
Actually my son in law got me hooked, he just upgraded his 911 five years old to a GT3( never been on the track) that is 2 years old and I go with him to Sebring and Homestead and help out as crew for the group of guys that go there. And I have a blast. I am getting goose bumps.

Nice! Sounds like you had a great time. Every 370Z owner should take their car to the track at least once to find the limits of their Z.

Thanks for sharing your story! I read it just before taking my Z to the track yesterday at Summit Point Raceway in WV. It was a blast. Lots to learn of course but I learned so much in just one class and a Hyperdrive. I'm stoked about taking it again soon!

glad to hear you had a good time.