If you're after unrelenting realism in every aspect of racing. You really ought be playing NetkarPro. Of course, it's sort of in a sorry state development-wise (maybe that will change, maybe not), but it has a hardcore mode where you have to wait while your car is towed back to the pits, you have to wait while your mechanics repair damage, you have to wait while your mechanics implement your setup changes.
Yes, that is realistic, but I think it's taking things a little too far personally. Some people swear by it though, and there's nothing wrong with that at all. Don't get me wrong, it's a fantastic sim, but as far as I'm concerned the only thing that really matters is the physical modeling of the car and the handling dynamics. Because it's simulated, we have advantages over the real world like not having to wait for all that stuff. I think that's a good thing.
You give a little, you take a little. Consult your doctor, use as directed, opinions may vary.
Love,
Aero