First thing to do would be to take care of the handling - best thing would be KYB shocks n king springs, seems to be the goer amongst celica modders. Add a swaybar too as the stock are pissy as. Then Panel filter n headers n full zorst.Thing is u cant have straight thru as this is way too loud . I tried it n its heaps over the 94dB limit - u need a resonator in there. Also, u cant chip as it isnt MAP and remappin the ECU doesnt really do much. Go to coil n better leads n runnin better fuel will also make a huge differnce. Have fun!