Duen, u mentioned earlier was that the rpm rev too highs when warming up time... i think this can be set down a bit... but i remember my friend told me that if using 20v engine needs a certain rpm/ or tilt that what "sotong", distributor r... dunno what that thing meaning... on a certain degree and it affects rpm also....
but mine engine never got that high... last time before my friend adjusted the airflow's screw and the distributor, my car warming up in just 1.2k rpm...then it will decrease down to 700-800rpm... around few secs later... not too sure but that is when i got the car back... and before that serious SVT common disease...air flow sensivity thingy... then nowadays, when warming up... it goes up till 1.4-1.5k rpm...then drops back to 800 rpm the lowest... can't get any lower...
as for the changing gear parts... ur rpm drops too fast or low... i think it has something to do with ur exhaust... how many inch u are using? i remember there was some others of our zth brothers here tested out with few set of custom piping right?... i think it was due to ur exhaust air were being pushed out too fast... u need to block it from flowing out too fast... ^_^