For anyone looking for an overlay/HUD that gives them fuel consumption calculations, tire wear, etc., go to your steam account. Click on rFactor2, then scroll down to "workshop".
Search for SMG HUD Pack. Subscribe to it, then go into Single Player/Options/Onscreen Display. Choose the one you like. Test it, try another if you don't like it. Lots of choices! There are non-vr as well as vr overlays. I currently use #29 (Dark VR with DRS). I hope this helps someone.