IMO, modding and lap times should be seen as two very distinct passions (unless you are a pro racing team that is
I used to be a mod junkie myself and I had tremendous fun doing it. However, modding can quickly get very expensive. Every time you change something on the car, the next weak link pops out, and you need to keep on modding. As I said, it can be a lot fun
until you reach the point where you start loosing reliability
After 18 years of tracking, I now consider that fast laps should be more focused around the driver. I keep on learning everytime I am at the track. Pro coaching is a good option. Once you have acquired enough experience, data loggers are also a great tool to improve yourself. You can compare your sector times and speed with your buddies and try to improve the next time out. For example, if one of your buddies is faster than you over a given sector, ask him to ride with you, he might be able to give you some pointers. By learning from each other, we can all improve
. I know it can become frustrating once you reach a plateau, but be patient a keep at it, you will have a brakethrough eventually.
My take: if modding makes you happy, than by all means keep on modding. If you want to be faster, work on your driving skills.