how can I optimize/tune up D13B2
 

Hello, i have a 1992 civic with D13B2 engine.

It is running on fuel and Liquefied petroleum gas, allmost all of the time I run on LPG (because its much cheaper in Lithuania :D )

These (d13b2) are pretty rare in Lithuania, and no one can share decent information about tuning them up, so anyway, i wanted to ask you, how can i tune up/optimize my carburetor engine, so it runs better, smoother and faster?

What i have done so far:
Air filter replace
Fuel filter replace(no effect while running on LPG :( )
Updated my LPG system (reductor, pipes, gas tank, gas and fuel valves, electronics, this **** costed me alot:( )
Changed my oil and oil filter
Changed the battery and battery clamps



Thank you for your time and information, and sorry for my bad english.