City has 2 cat converter .
1 primary near engine .
Other secondary below car floor area.
Get a empty primary cat converter casing in good condition ,might cost you 1000-2000rs .
Take out your oem primary cat Converter with casing and save it in you store and install the empty casing in its place.
Thats when you started feeling the power of Honda City 1.5 ivtec and will feel the vtec kiked in .
Done this in my city. Now my Citys average fuel consumption is 14.3km/l before its 11-12km/l
Note City has secondary cat con which prevents air fuel mixture imbalance and also your car will not run rich as happens with most of cars after cat removal.
Also no air pollution will occur.