Are you talking about wheel lag in Shift 2? If so, you're absolutely right... but there are plenty of suggestions out there for setups.
In just about any game you play, search google for wheel setups.
I think this one is related to the EX (although it might be for the DFGT).
Steering Deadzone 0
Steering Sens 100
Acc deadzone 0
Acc Sens 100
Brake deadzone 0
Brake sens 100
Speed sens 100
Speed sens(drift) 100
In Logitec Profile
FFB setting.. whatever you want, mine are 15,1,1
Centering force 50
TURN OFF " allow game to change settings"
Once you've got it going for Shift 2, it will be a while until we see you (as the game is awesome - check out my review
Also, you've said 'sim' but then talked about playing the Run. iRacing is sim, Run is arcade. But here's a good list of titles that end up closer to the sim camp.
RACE (the whole series is excellent, Race ON, Race 07, STCCII, GTR Evolution, but only the base install is really needed.)
Test Drive Unlimited (this will be a controversial choice) - Gives you two perfectly mapped actual islands (Oahu in Hawaii and Ibiza), no other game lets you drive so endlessly.
DiRT - any of the series is worth getting (although I prefer 2) but be warned, in-cockpit is brutal
ToCA Race Driver 3
iRacing is a heavy sim man, very few get their dollars worth race wise.. I'm subbed for a year but haven't raced in several months!
Anyway, good luck, let me know how you got on.