yes, its the same fluid for both systems as I recall

I'll check fluid level then, it must have something to do with that.

How deep were you into the clutch? Sometimes when I'm at the line, because I like to keep the clutch disengaged right before the point of engagement, and I'm holding 4k or so rpm, it sometimes catches and rolls me foward very slowly. Its hard to keep the pedal right there with the heavy pedal pressure.

since I was so desperate of always fouling, I got to the point that I just floored the clutch, but it didn't work either.

But I used to do the same thing that you do, just keeping the clutch barely disengaged

Mine has always done this. It seems to vary depending on lane and where the groove in the track is that day. To cure this I put a line lock switch under my clutch pedal so when I stage the car, I slightly push on the brake, push the clutch all the way down and release the brake. Bring my revs up to where I need them and launch on the 3rd yellow. I wouldn't worry about it unless you are having shifting issues. If you are having shifting issues then the clutch isn't releasing all the way or you have a slightly warped flywheel.

Did it happen in both lanes? Just curious..I know at Cordova I can't just sit deep staged because the pavement is uneven and I will roll slowly forward (it stops once I hit the low spot though)...

Does your car continue creeping or is it 'rolling' a short bit?

First thought I had after reading this is that the track isn't perfectly level. Same thing happens at my track. I have to use the hand brake to hold the car, sucks.

track is level, there was 2 other s197 there and they didn't roll... I topped my break fluid, see if that helps, I'll be going to the track June 21st, the bad thing is we are expecting the temps to be in the upped 100's :(

That heat hurts, man. Hopefully, its a dry heat. If so, at least it won't be quite as bad as this +90% mess in NC. Still sucks though. I'm already ready for the fall.

i notice the same thing with my DSM from time to time. It seems like sometimes the clutch doesnt disengage all the way, but i expect problems from an 18 year old DSM..not a fairly new mustang. Ive been to a few tracks that have a sloped starting line, but usually not enough to make a huge difference unless someone is pissing around staging.