Thanks for the suggestion, but we're not going to track turbo. We've talked about this already quite a bit in the forum, and we have a FAQ entry about it here: Why don't you track more vehicle details?
We know that the level of detail we track here at Fuelly is not going to work for everyone, but we also feel like we have a good balance as things stand now.
People are free to include more detail about their vehicle in their title or description. That will help people who want to do more digging to know why a particular vehicle might be getting better or worse fuel economy than others.