Hi, Rodney, I have to take a small issue with your logic here....there's a huge difference between the duty cycle of a racing engine...torn down and rebuilt after every race, and a passenger vehicle which must last through many years of various conditions, including possibly owner neglect in frequency of oil changes, etc.

The duty of the filters on the race engine is to keep the oil clean for a few hours, and to do so with minimal pressure drop. They probably set them up in parallel pairs. Any one of a dozen filters can do that. The one on the engine is the one that paid the car owner the most to put their decal on the side of the car - ie: bragging rights.

The Volvo engineers chose the Mann for many reasons, (economics being among them), but it is also a very high quality unit.

As is the Wix, no argument there. But the race track is, in many instances, not the proper test of a component's suitability for the 'street'.

Now stepping down from my soapbox......


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Bob (son's 81-244GL B21F/M46, dtr's 83-244DL B23F/M46, my 94-944 B230FD and 89 745 (LT-1 V8); hobbycar 77 MGB, and a few old motorcycles)