1) what would you prefer the new a/c oil filter or the purolator classic?
10 years ago the Purolator was mid pack and the AC head and shoulders above it, half again as much media. Much has changed since then.
2) What does everyone think of the e-core ?
They are new, different and gasp, aruugh they are all paper and plastic inside. Objective data showing a problem or superiority? None. Personal experience with them? None. I keep hoping to fine one that fits my truck.
3) Are the new a/c delco filters made by champ?
Ah, perhaps the clearest answer. They all seem to be now. Earlier this year there seemed to be some made by Wix around. If you look inside and see a black plastic cage aistead of a metal tube, they are a made by champ Ecore.
$) Who made the older a/c filters?
The low bidder. When? When Delphi was owned by GM, they made many of them. 5-10 years ago, BBIOTG, I chopped open many of them and found a wide range of constructions.
If you have a GM product, the engine bypass protects it from the Purolator dome end bypass.
Champ is an American company owned making their products here.