Am I missing something?

[2James1]

Originally Posted By: sayjac
Originally Posted By: 2James1
Originally Posted By: sayjac
What makes you think the BD+ is less efficient that the P1?

I was only basing the efficiency on what the manufacturer states. FWIW

Which according to the Bosch website is 99.9%, with no published corresponding micron level. The P1 is also rated 99.9%.

I was thinking the Bosch distance plus was rated at 25 microns vs the pureones 20 microns. Maybe I got confused and was thinking bout the new purolator synthetic filter vs. the pureone.

 

[TC]

If your primary goal is preventing metal-to-metal wear (which obviously it should be), simply use the finest filtering media you can find, not that it's easy determining what's "fine" or not. Don't worry about capacity: Unless you're going to extreme intervals (something well beyond 10K miles), or live on Dust Avenue in Dust City, USA, capacity will never be an issue for you. Filter particulate capacities have a good tolerance for abuse factored into them, and are made to accommodate (within reason) those few who change oil far less frequently than needed.

 

[skyship]

WOW! The advertising folks will love you for accepting filter efficiency figures so easily, because most of the filter figures are final filtration figures, NOT THE MORE IMPORTANT INTITIAL FILTRATION figures, that manufacturers seem to avoid publishing.
Filters might not be so important when an engine is in good order, but can be more important than the oil if something goes sour in either air filtration, OCI, TBN depletion or main block terms.
Unfortunately trying to figure out which filter is best and how often to change it is a very complex calculation. In general terms you will find it very difficult to beat the manufacturers recommended oil filter changed at the recommended FCI. Most of the debris that passes by a filter does so when it is almost new, so the big issue is how to avoid changing filters too often without taking any chances on blocking the filter, in combination with what the all important initial filtration performance is.
Any filter company can make a filter with a very high final filtration performance, BUT most of them can't make one with a real good initial new filter performance. Many of the long life filters and even by-pass filter installations do not work as well as advertised because the initial clean filter performance is no better than a normal high quality filter.

Originally Posted By: sayjac
Originally Posted By: 2James1
Originally Posted By: sayjac
What makes you think the BD+ is less efficient that the P1?

I was only basing the efficiency on what the manufacturer states. FWIW

Which according to the Bosch website is 99.9%, with no published corresponding micron level. The P1 is also rated 99.9%.

 

[Sayjac]

In the absence of any other proven published standard, I accept ISO test standard results which are the standard for detemining filtration efficiency. The current ISO 4548-12 is the current accepted standard for filter testing and what is used and cited in filtration test efficiency results. A standard you incorrectly referred to as snake oil when the data was illustrated/published in Amsoil testing of oem filters, and the related thread here.

If you choose to believe and follow some nebulous, unpublished, unproven methodology for determining filtration efficiency, your choice. I'll stick with the current certified scientific ISO standards used for determining and publishing filtration efficiency.

 

[Jim Allen]

Also, initial efficiency period doesn't last long. The big holes plug pretty quickly. I hesitate to quote this without having verified it more... though it sounds right to me... but I was recently quoted a statistic that says an oil filter reaches to within about 10-15 percent of it's final efficiency within the first 10 percent of operational life. I.e. sharp climb and levels off.

The initial efficiency figure can be somewhat nebulous as well because you have to run a standard ISO test, just aborted to get an early reading. The usual procedure is to circulate a specific amount of test contaminant... smaller than the amount required to achieve max rated DP. Don't know if ISO has a specific procedure for it. I'll ask. I have been talking to some oil filter people lately and each company seems to have it's own way of determining initial efficiency and they aren't easily comparable. I learned the same is true with air filters.