Aftermarket air filter contributing to major engine damage

Originally Posted by TiGeo
That famous report (Spicer?) that makes the rounds every once in a while shows the K&N to have a~96% filtering efficiency vs. the AC Delco (?) at 99%...it's not an argument. However, what is an argument is whether 3% less efficiency makes f all of a difference to your engine.

Actually it's a 300% difference in efficiency. 1% of dirt getting through vs 4%.
 
Last edited:
Originally Posted by circuitsmith
Originally Posted by TiGeo
That famous report (Spicer?) that makes the rounds every once in a while shows the K&N to have a~96% filtering efficiency vs. the AC Delco (?) at 99%...it's not an argument. However, what is an argument is whether 3% less efficiency makes f all of a difference to your engine.

Actually it's a 300% difference in efficiency. 1% of dirt getting through vs 4%.


I guess I'm thinking of it differently - I'm going with there is 100% available dirt (I'll use numbers so say 10g) to get in over the test and the AC Delco filters 99% (9.9g) of it out and the K&N filters out 96% (9.6g) of it. The K&N lets 0.3g more dirt in. 0.3/10g = 3% more of the total. 0.3g/0.1g = 300% more relative to one another. However you want to make this work.
 
Originally Posted by TiGeo
Originally Posted by circuitsmith
Originally Posted by TiGeo
That famous report (Spicer?) that makes the rounds every once in a while shows the K&N to have a~96% filtering efficiency vs. the AC Delco (?) at 99%...it's not an argument. However, what is an argument is whether 3% less efficiency makes f all of a difference to your engine.

Actually it's a 300% difference in efficiency. 1% of dirt getting through vs 4%.


I guess I'm thinking of it differently - I'm going with there is 100% available dirt (I'll use numbers so say 10g) to get in over the test and the AC Delco filters 99% (9.9g) of it out and the K&N filters out 96% (9.6g) of it. The K&N lets 0.3g more dirt in. 0.3/10g = 3% more of the total. 0.3g/0.1g = 300% more relative to one another. However you want to make this work.


Quoting myself from the other discussion on this matter:
Originally Posted by OVERKILL
Originally Posted by TiGeo
Originally Posted by OVERKILL
Let's look at the dirt passed and time to restriction limit data. The duration of the test was 60 minutes and during that period, the amount of dirt passed by the Donaldson unit was 0.4g. The K&N passed 7g of dirt within 24 minutes and hit the restriction limit.

If we break this down to g/minute passed, a simple metric, we can perhaps gather some clearer data comparing the most efficient filter in the test, which also loaded up the slowest, and one of the least efficient.

1. Donaldson PowerCore: 0.0067g/min loading rate
2. K&N oil cotton gauze: 0.2917g/min loading rate

This means the Donaldson is 43.5x more efficient.

Ignoring the loading limit, if we just look at the performance within a 6 hour window:

1: Donaldson PowerCore: 2.4g of dirt passed
2. K&N oiled cotton gauze: 105g of dirt passed

That's a HUGE difference. The Donaldson would have to be run for 262.5hrs; 11 DAYS to pass the same amount of dirt as the K&N, or, looked at from the other direction, the K&N passes in 8.2 minutes what it takes the Donaldson 6 hours to pass.


I am looking at flow - does the Donaldson flow more air than the K&N? I doubt it. The K&N absolutely passes more dirt...it has too.


Given we are looking at filters all for the same application, and the Donaldson was OEM, meaning it was more than appropriate for that application in terms of flow, and also managed to pass the most air while simultaneously pass the least amount of dirt (which is why it was the only one that made it to the 60 minute mark) flow only becomes an issue when you are using a filter that from the get-go, isn't sufficient for the application. The application in this case was a Duramax, so conceivably if you could fit the Duramax filter to your ride, you could benefit from both traits here.

Filter area, due to design, on the Donaldson, which is completely different from other designs, is quite large. It's filter area that determines flow at a given restriction, which is the same reason you see more media crammed into the higher efficiency oil filters. So you have two options here:

1. Reduce efficiency, increasing flow
2. Increase surface area, increasing flow

We know the K&N does #1 without doing #2, in fact they may reduce surface area given how quickly it hits the restriction limit in the test. Donaldson clearly does #2 without doing #1, given they have the highest efficiency of any filter covered.
 
Originally Posted by maxdustington
Originally Posted by edwardh1
Possibly driving it too hard then parking it immediately while very hot
They didn't make Bluetecs in the 80s, boomer.


How cringe.
 
Hi chaps.

Was talking with a customer today, we were talking about diesels and stuff.

He said a current vehicle of his, equipped with the Mercedes Bluetec platform, had some kind of aftermarket type air filter installed at some dealer. Apparently this modified the pressure drop in the intake, which lead to fuel combustion issues, which clogged the DPF, allowed soot to get into the turbo and cooked that too. When he took it back they ended up offering him 20k off a new vehicle because with that much alleged damage who wants to take up the tab on the labor cost of fixing all that?

Sound plausible? I think so, but I can't sleep tonight without thinking about it, if it's true.
 
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