satria neo 1.3 auto.. currently installed 4-1 header. any suggestion? pm me da best price..

Bro M_fa, i have an auto satria neo 1.3 campro.
Currently i had already remove the original extractor with the catcon and replaced it 4-1 extractor(the short one i guess, just plug n play one) because the previous mechanic said 4-1 is more suitable since it provide more pickup to 1.3 auto..
i did change the muffler to straight flow before.. but since i'm tired with the noise i change it back to original one.. it's been quite sometime that i used the car that way.. and i notice that the fc electronic metre had gone crazy.. sometime the numbers going up even though the petrol is decreasing and vice versa..
The fc itself.. not that good. The perfomance is only quite good when overtaking.. hill climb.. quite sad though.. huhu..

So, is there any way to solve this? i mean to have better fc, increase in perfomance as well as fixing the crazy fc metre.. hehe~
maybe you could pm me your best setup for 1.3 auto.. because i kinda heard that setup for 1.3 auto is quite different since the engine is not so powerful.. huhu~ thanks bro!!


p/s: SORRY for the long explanation though.. huhu~