As we're talking Delta S4 here, I purchased a French produced DVD (AH Video Concept Communications), simply entitled "Groupe B", while at Autosport International, featuring several privately entered S4s "en course de cote" "in Hillclimb" "zum Bergrennen" (Berg Cup).
The DVD covers the years 1989 to 2006 and is a very healthy 2 hours in duration.
The cover features all the usual Group B suspects, but luckily for us Lancia fans, the S4s feature heavily and an 037 rallye also appears briefly.
Thankfully there is no commentary, just those incredible supercharger and waste-gate noises.
One S4 is owned/driven by Bruno Ianniello and another by Sascha Geninasca and they're not pussyfooting around either!
I recommend you track down a copy, despite the continuity not being the best, e.g.. wet road, dry road, wet road, etc.
http://www.videoconcept.com/magasin/product_info.php?cPath=23_28&products_id=639