Synthetic

[SubieRubyRoo]

Originally Posted by tundraotto
As the filter gets more clogged its efficiency goes up...but the bypass does not open.


That's what you would think, but ZeeOSix has previously posted test data that proves that filter efficiency goes down as it is loaded, until the point it is about 99.8% "full" where it approaches 100% filtering efficiency, and then drops to zero after the filter media is plugged and the filter is in bypass.

 

[kschachn]

And I also wondered what a "super tight mesh" filter was.

 

[blupupher]

Originally Posted by painfx
Originally Posted by Bettez88

Is the ultra worth $14 when the Mobil1 is only $10 at Walmart? Which would filter better? And what about Mobil1 clones like the ecogard synthetic filter?


Fram Ultra $14? I think the price is same as Mobil 1 at Walmart.



Originally Posted by kschachn
The Fram Ultra for my Sienna is $8.97 at Walmart, nowhere near $14. The Mobil 1 is $9.97.


Well I went and looked, and many Ultra cartridge filters do cost more than the canister.
A XG10855 for my Santa Fe is $14.47 at Walmart, M1 does not make a filter for it, so can't compare.

 

[ZeeOSix]

Originally Posted by SubieRubyRoo
Originally Posted by tundraotto
As the filter gets more clogged its efficiency goes up...but the bypass does not open.


That's what you would think, but ZeeOSix has previously posted test data that proves that filter efficiency goes down as it is loaded, until the point it is about 99.8% "full" where it approaches 100% filtering efficiency, and then drops to zero after the filter media is plugged and the filter is in bypass.


Once people understand how ISO 4548-12 calculates the final efficiency rating, which is an average over the duration of the test, then it makes sense that filters with lower efficiency are most likely sloughing off captured particaks as the filter loads up and the delta-p increases.

The filter in the example below would have an ISO efficiency of around 75% at 20μ (average of 90% and 60% efficiency at 20μ).

 

[SubieRubyRoo]

That's the one, Zee. Thanks!

 

[Linctex]

Originally Posted by SubieRubyRoo
Originally Posted by tundraotto
As the filter gets more clogged its efficiency goes up...but the bypass does not open.


That's what you would think, but ZeeOSix has previously posted test data that proves that filter efficiency goes down as it is loaded, until the point it is about 99.8% "full" where it approaches 100% filtering efficiency, and then drops to zero after the filter media is plugged and the filter is in bypass.


That was Purolator data, if I remember correctly. (a non-synthetic filter)

I'd like to see more tests done than just that one.

More tests = more reliable data

 

[ZeeOSix]

Originally Posted by Linctex
Originally Posted by SubieRubyRoo
Originally Posted by tundraotto
As the filter gets more clogged its efficiency goes up...but the bypass does not open.

That's what you would think, but ZeeOSix has previously posted test data that proves that filter efficiency goes down as it is loaded, until the point it is about 99.8% "full" where it approaches 100% filtering efficiency, and then drops to zero after the filter media is plugged and the filter is in bypass.

That was Purolator data, if I remember correctly. (a non-synthetic filter)

I'd like to see more tests done than just that one.

More tests = more reliable data


Yes, but all media types increase in delta-p to some degree as the media loads up - some worse than others. As said previously, the amount of debris holding under increased delta-p is the key to ensuring a filter remains efficient over the life of the filter. Synthetic media seems to be most efficient and has the best holding capacity with smaller delta-p.

Knowing how the ISO 4548-12 efficiency is calculated (the average efficiency over the loading period), a filter that is ISO rated at 99% @ 20u by definition has to be pretty efficient over the entire loading period in order to maintain a "start-to-end efficiency" that high. Filters that slough off captured debris badly as the delta-p increases will never have a high ISO efficiency rating.