I notice every time I set my tip to Manual and take it for a run I find that the car is for always short shifting. Meaning before I make a move to shift to the next gear it will shift by itself say on 5000 or 5200 revs.
It is summer and it is Africa so were are talking of temperatures of around 30 to 33C (86 - 91.5F). However, I am sure even with colder temperatures I have experienced it.
The problem is lessened by switching to Automatic?
Anyone else experienced that problem before?

(K24's with headers and exhaust and I am sure some sort of flash by the previous owner "about 90 kPa "13 PSI" boost")
Thanks in advance