I'm curious to know, how come i'll be driving my '90 RS 305 TBI and i can push the throttle about 2/3 down and feel a good push and then again at 3/4 throttle push again and feel another good jump and then other days i'll try the same thing but i don't really feel a good push but more of a gentle nudge, i am thinking it has to do with the temperature of the engine and the outside temperature at the time, any ideas? thanks in advance

is each test being due in the same gear and rpm/speed?