...do to achieve this? I have Toyota Corolla AE89 SE Limited with a 5A-FE 16-Valve 1500cc EFI engine. The engine is quite old now as its registered a long time back.I'm in Bangladesh.Here i drive the car both on Octane and on CNG.I overhaulled the engine a few days back.The insides where the pistons were,was in a bad condition.I increased the diameter of that and installed larger pistons.Using CNG runs the engine really hot so i'm gonna install a second radiator. I'm planning to install an ecu (in bangladesh u dont really get the aftermarket ecus, i got 1 of a 5A-FHE, i think i'll buy that),an aftermarket air filter,iridium-platinum plugs,aftermarket spark plugs. ANY ADVICE WILL BE REALLY APPRECIATED!!! Thanks.