My car shifts smoothly on the street and about the first lap on track, but after that, when things start heating up I imagine, every shift feels like I'm shifting with the clutch half disengaged or something... basically VERY notchy and I have to literally jam the thing in gear... no grinding though.

I don't think it's the fluid anymore because I've used both Honda MTF and Amsoil Syncromesh MTF with no change at all, and all the other guys who track their car with those fluids don't have any problems at all. So fluid aside, what else could it be?

 

No leaks on CMC? You never mentioned checking your clutch fluid level

 

Does this happen on the streets too? When your just driving normally?

Did you try adjusting your clutch pedal? I know you said you think it may be when the cars warmed up but I am just throwing the idea out their.

 

Changed your clutch fluid lately?

 

I think the general notchy feeling is from the output shaft needing to be regreased rather than the oil or the shifter being greased. As I recall, these are the three main culprits for notchy shifting, and after changing fluids and regreasing the shifter, the last thing to try is greasing the output shaft, which does not come well greased from the factory.