Need sbc help!!

[cstm68]

i have a small block 327 with a saginaw 4 speed in my 68 and i cant get it to run right. i has been running great all summer. now it runs great until it gets up to temp. once up to temp it idles rough and if i try take off on any sort of incline it lugs way down and i need to feather the clutch as if i were taking off in 2nd or 3rd gear. if i punch the throttle it hesitates and sputters. there is also a tick noise that sounds like it is from the drivers side header but is only there when the engine is hot, but that has been there for a while.

I have checked for vacuum leaks and could not find any, re timed the engine and replaced the fuel filter. anyone have any ideas??