Has anybody noticed when your driving 115 + that your clutch feels a little spongy after and then goes back to normal after 10 seconds or so of slowing down

 

You mean driving 115 mph on the track?

When was the last time your clutch fluid was flushed?

My guess the spongyness is due to the additional heat generated by the engine which causes whatever moisture is present in the fluid to boil, thus generating air in the line.

There's a tsb for the 370's that involves changing out the stock fluid for the gtr brake fluid (DOT 4). IMO, any decent high perf dot4 brake fluid with a high wet boiling point should work for street applications. For track, you probably
want something with an even higher wet boiling point.

 

always add on track~ ^^

 

Yeah on the track. Thanks for the info just bought the car in February and I need to change the fluid

 

^ Also changing to a SS clutch line may help.