You mean classify the car and their models on the forums? The cars and their models are already listed in New Cars section. If you mean search on Forums all the topics related to that car's model, then that's too general as in the search results you would see many topics (such as Honda Vs Toyota battles on the forum) or some information on Toyota Corolla US model which has little relevance.
The Fan clubs are a good place to see all the basics of a particular car.. such as Honda City Fan club or Vitz fan club, where the owners of these cars are discussing the technical details such as recommended oil, parts, mechanics, modifications etc. However it would be great if that kind of information is available for all the cars and their models available in Pakistan and users can go and contribute in those threads whenever they feel like talking something related to that car, rather than creating a new thread. That would give a very great informative database of that model at one place.
I have another suggestion on the forum format, which I think would not only reduce the number of different threads made on the forum sections but also will provide info in an organized effective manner.
Rather than having different sections on CNG, parts, tyres etc, let's have a section with the name of 'Cars'
Under cars you have subsections each of all the car models available in Pak. E.g.
1. Honda City Manual
2. Honda City Vario
3. Honda Civic VTI manual
3. Toyota Corolla XLI/GLI
4. Toyota GLI 1.6 Auto
5 Toyota Altis 1.8
If you click on a particular car, then different models would come, e.g if you click City Manual, 5 options will come 2009+, 2006-08, 04-05 etc
After clicking one 1 of them, then users can choose one of the following sub-sub-section: Engine, CNG, Tyres, Mechanics, Fuel efficiency, Transmission & Suspension, Spare parts, Modifications, and any other topic. These sets of sections to be available for all car models. Any user who wants to discuss or ask any issue would just have to search his car model and ask the question in relevant section, where the chances are high that some users have already provided their feedback on his problem in hand.