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Performance Air Filters

I used to have a performance air filter in my w210, and every time it was time for service I replaced it with the original filter just for the service. And swapped back afterwords just so the dealer should not give me any hassle.
 
Race cars have regular engine strip and rebuilds - do you feel lucky? :D

Open up a genuine Mercedes air filter, cut out the paper and measure the surface area and then do the same with your 'performance' filter.
I'll put money on the mercedes filter having better filtration down to smaller pariculates *and* a greater surface area, meaning it'll be able to filter more cm3/s.

Performance filters are for boy racers in their saxo's.

Suggest you put some faith in the Mercedes multi million Euro R&D dept rather than wisdom of fred and larry with a surplus of foam and 'magic oil'.

Sorry but i'm with Baldguy after 30 years in motorsport and performance engines OEM manufacturers filters are pants. I bet MB don't even do the R&D on the filters they will trust in the filter manufacturer as all other car makers do who will optimise their production process which compromises the filter.

I also think you are confusing several issues here, race cars do not get regular engine strip downs, my rally car has not had one in 3 years, the greater the surface area of a filter means it will restrict the airflow more and its filtration rate will be lower than that of a performance filter although I accept the air the other side of the filter will be cleaner.

You have to ask the question why fit a performance filter, then do you fit a wet one or a dry one?

Take a dry Green cotton Panel filter for example it will be far more efficient and provide greater airflow and cleaner air than any OEM paper filter, engine will be more responsive, mpg may increase, bhp may increase

I'm not a fan of wet filters like K&N but for some reason when you say performance filter everyone thinks of K&N and Oil, there are far better out there.

If you want to get the best out of your engine then bin the paper filter and put in a performance one every car I have ever owned has had one and I have had no issues in 30 years, all I am saying is be very careful on your choice of performance filter.

Just to clarify I am talking about replacement panel filters and not the cone type that replace the airbox, they really are a waste of space and a good way to kill and engine.
 
Your performnce filter will *not* be doing as good a job at filtering the air as the one designed for the car and I suspect this would be good enough reason for declining any engine related warranty claim should one come up.

I had a car that covered 214,000 miles before I sold it which had a performance filter fitted from new. The engine was perfect when I sold it on (the guy tells me it's on 220,000 miles now and still going happily to 8k rpm without using oil or showing rattles etc...)

Some aftermarket filters are more efficient than others in airflow and filtration. There's 2 'panel' filters on my AMG, are there any recommended types fitted by other people on here?

Interestingly enough the car has just had a full service and I swear it is sluggish now. It doesn't pull hard at low revs and takes until maybe 3k rpm before it takes off.
 
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Myself and BaldGuy have the ITG ones supplied as part of our recent Engine remaps..

The ITG ones are foam and 'magic oil' arent they?

@fianna how many miles has your race engine done in 3 years? Likely to be the same as most road cars do in a month or two. I stand by what I say when I say race engines get stripped and rebuilt frequently.

IIRC if you measure the surface area of a standard airfilter and then look at the engine capacity of each cylinder and work out the absolute maximum throughput of air at maximum revs you'll find that the standard airfilter can cope with the demands multiple times over. This being the case, what exactly are you achieving by fitting a filter that allegedly can offer more throughput? Look at the science - the rest is marketing spin.

These foam/oil based filters cannot filter as well as the paper type and they also rely on regular re-oiling of the foam (like every few hundred miles) as the oil very quickly dries out due to being drawn into the manifold.

On BalGuys engine, I believe it has a fancy variable inlet manifold that is controlled by the ECU which monitors inlet manifold pressure. A great deal of development has gone into this and bunging a foam based filter that will filter less and introduce contaminents into the manifold and cylinder with an increased likelihood reducing the effectiveness of the manifold flaps and also the likelihood of damaging the upper cylinders - it makes no sense at all and is of no surprise to me that mercedes makes this stance.

But if you think you know better than Mercedes (and all the other car manufacturers) then go ahead. I'll stick to the science however.
 
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I think the problem here is "performance", it isn't specific, it applies to go faster stripes, turbo stickers, and cheap and nasty air filters...

A genuine performance air filter is better than OEM, and costs more than OEM (higher quality + lower production volume) but a clean OEM works much better than a dirty performance filter, which reminds me, time I checked my air filter too.
 
I thought that the filters fitted to AMG engines as standard were perforamnce filters anyway - I seem to recall the part numbers were different
and I believe the colour of the filter was different.

Check it out.

(and the price was greater ?)
 
The ITG ones are foam and 'magic oil' arent they?

@fianna how many miles has your race engine done in 3 years? Likely to be the same as most road cars do in a month or two. I stand by what I say when I say race engines get stripped and rebuilt frequently.

But if you think you know better than Mercedes (and all the other car manufacturers) then go ahead. I'll stick to the science however.

I agree the mileage of about 3 months on a road car but about 1000% more stress, race cars do not have regular engine strips (unless they fail) not even in F1 it's just a myth.

I only ever stick to Science and Engineering thats what I do and don't forget some manufacturers on their performance range fit aftermarket performance filters as standard including some K&N ones.

With all the B*llocks and BS Mercedes delaers talk in the UK I wouldn't believe a word they say, do you seriously think they run paper air filters on their DTM race cars? I rest my case
 
Sorry but i'm with Baldguy after 30 years in motorsport and performance engines OEM manufacturers filters are pants. I bet MB don't even do the R&D on the filters they will trust in the filter manufacturer as all other car makers do who will optimise their production process which compromises the filter.

I also think you are confusing several issues here, race cars do not get regular engine strip downs, my rally car has not had one in 3 years, the greater the surface area of a filter means it will restrict the airflow more and its filtration rate will be lower than that of a performance filter although I accept the air the other side of the filter will be cleaner.

You have to ask the question why fit a performance filter, then do you fit a wet one or a dry one?

Take a dry Green cotton Panel filter for example it will be far more efficient and provide greater airflow and cleaner air than any OEM paper filter, engine will be more responsive, mpg may increase, bhp may increase

I'm not a fan of wet filters like K&N but for some reason when you say performance filter everyone thinks of K&N and Oil, there are far better out there.

If you want to get the best out of your engine then bin the paper filter and put in a performance one every car I have ever owned has had one and I have had no issues in 30 years, all I am saying is be very careful on your choice of performance filter.

Just to clarify I am talking about replacement panel filters and not the cone type that replace the airbox, they really are a waste of space and a good way to kill and engine.

This bit confused me.

If you increase the surface area of a filter you generally increase the number of pores, thereby increasing the flowrate through the filter (pore size being held constant). The cleanliness of the air will be determined by the pore size of the filter, not their number.

Or do I have that wrong?
 
Race cars run slicks, because they have for more grip (in the dry) so does this mean that we should all run slicks on our road cars, along with race car air filters?
 
This bit confused me.

If you increase the surface area of a filter you generally increase the number of pores, thereby increasing the flowrate through the filter (pore size being held constant). The cleanliness of the air will be determined by the pore size of the filter, not their number.

Or do I have that wrong?

I was refering to the whole surface area of the paper element compared to the whole surface area of a cotton or foam filter.

If you consider the surface area of the pores then yes you are correct the greater the area the greater the flowrate and yes the pore size determines filtration performance from a contaminants point of view.
 
Race cars run slicks, because they have for more grip (in the dry) so does this mean that we should all run slicks on our road cars, along with race car air filters?

:doh: If you could guarantee the roads would never be wet then yes. But we use road tyres because they are a compromise and perform in all conditions but even accross road tyres you can get virtualy slick if you look at Toyo Proxies again it optimises performance in the dry. It's all about how you want to set your car up and it's personal to the individual there is no right or wrong.
 
So is the general Consensus that aftermarket filters are better or worse than standard.....

IMHO Miles better or the companies manufacturing them would be out of business by now. Theres plenty of independent tests out there if you Google it.
 
I was refering to the whole surface area of the paper element compared to the whole surface area of a cotton or foam filter.

If you consider the surface area of the pores then yes you are correct the greater the area the greater the flowrate and yes the pore size determines filtration performance from a contaminants point of view.

So how does the surface area of a paper element differ from that of a foam one?Are the pores not uniformly distributed on the paper element such that when increasing the surface area (of the paper element) the number of pores does not increase?

Or do you mean the number of pores per unit area will always be greater in the foam or cotton filter?

What do these automotive elements filter down to, generally, i.e. what is the pore size?
 
IMHO Miles better or the companies manufacturing them would be out of business by now. Theres plenty of independent tests out there if you Google it.

Not if the numbers of new customers taken in by the sales pitch continues.

I'm not saying that's the case here, it's just I've never liked that argument for justifying the validity of a product...
 
I agree the mileage of about 3 months on a road car but about 1000% more stress, race cars do not have regular engine strips (unless they fail) not even in F1 it's just a myth.

What, more air stress on the filter? :dk: Depends on the type of racing, top fuel drag racers rebuild their engines as frequently as every 30-40 seconds. Dakar racers have engine swaps daily. It is not a myth - it is fact.

I only ever stick to Science and Engineering thats what I do and don't forget some manufacturers on their performance range fit aftermarket performance filters as standard including some K&N ones.

i'ved never seen K&N's fitted as standard - care to name nd shame as it might shed light on the reaon behind this.

do you seriously think they run paper air filters on their DTM race cars? I rest my case

Interesting point,but a flawed one. Lets just suppose they do (which I doubt in all honesty) you are forgetting that a typical DTM race engine will likely do less than 2000 miles between rebuilds.

How many miles will an F1 engine do before a strip down do you think?
 
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What do these automotive elements filter down to, generally, i.e. what is the pore size?
[/S-TAG]

Aha, the 64 thousand dollar question, with ALL filters.

The answer (if given) is not a single number. It should be...

75% of all particles 10 micron
95% of all particles 20 micron
99% of all particles 30 micron

as the "Holes" in a filter vary in size and quantity (distribution)
 
I thought that the filters fitted to AMG engines as standard were perforamnce filters anyway - I seem to recall the part numbers were different and I believe the colour of the filter was different.

They looked like white standard filters to me. Not that I'd know the physical difference by looking
 
What, more air stress on the filter? :dk: Depends on the type of racing, top fuel drag racers rebuild their engines as frequently as every 30-40 seconds. Dakar racers have engine swaps daily. It is not a myth - it is fact.



i'ved never seen K&N's fitted as standard - care to name nd shame as it might shed light on the reaon behind this.



Interesting point,but a flawed one. Lets just suppose they do (which I doubt in all honesty) you are forgetting that a typical DTM race engine will likely do less than 2000 miles between rebuilds.

How many miles will an F1 engine do before a strip down do you think?

No more stress on the engine :doh: a top fuel dragster running a paper element now that would be funny:) we were talking "normal" motorsport not extremes like drag racing and Dakar cars so we'll stick to saloon type car racing for the purpose of the discussion where frequent engine changes or rebuilds don't happen becuase under current regulations you get penalised for it in most formulas an engine has to last for so long.

Seat certainly used to fit K&N as standard to their Cupra models, not sure if they still do but they definitely did in 2004

Yep an engine rebuild for a DTM car is about 2000 miles and for an F1 car it's about 800 -1200 depending upon the circuit succession as an engine has to last for 2 races.
 

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