danlim@
4-2-1 gives better response and 4-1 gives a higher top speed. it wasn't the tyre problem. somemore, with proper pnp, engine should be more responsive.
perhaps, down to the material quality of the 4-2-1 setup. low quality material will caused more carbon deposit after a few months of usage.
thus, caused the loss of power.
what is your 17" tyre width?
last time my car idle for a month and become less responsive, i reset the ecu, drive the car in aggressive way and bingo! it back to aggressive
again
btw, that's mean you need to reflash with steven already
WhitE LighteR@
we all do have a choice but waja is easily the best handling and most spacious car for that price ( due to government's protection

).
i bought a waja because it's cheap and the stock one can easily handle the sharpest corner at karak highway at 140km/h
already upgrade thou but for some sentimental reason, still keep and even mod my waja.