I've used K&N filters in the past and have one fitted in my wife's Roomster but this thread reminds me that I ought to check my ITG filter to see if it needs a clean.

It has done around 5,000 miles in my Octavia vRS followed by 13,000 miles in Kevin. Might be a bit clogged up by now.

PS> I'm just using an OE panel filter replacement at the moment.

http://lyxus.net/irra was the best price I came across.

Ordered 6pm Boxing Day - arrived yesterday!

http://lyxus.net/irra was the best price I came across.

Ordered 6pm Boxing Day - arrived yesterday!

Not a bad price.

I assume that will fit both the 140 and 170hp engine.

Be interesting to see if you notice any difference, my money is on you will!

Let us know what you think ....hopefully I wont be the only voice in the wilderness

Pedant warning (2).

For a controlled, and therefore scientific, test you'd need to compare running with the OE 'dirty' filter, running with a brand new OE filter, and running with the K&N.

Let us know what you think ....hopefully I wont be the only voice in the wilderness

They DO work but what has been said several times and seems to be ignored each time is, if the OE filter is more than up to filtering more air than can be used by a diesel engine then what is the point of spending more money (not to mention the fact you need to clean it) just to filter even more air that cannot be used??

I have used K&N filters with good effect on NA rally cars, on a diesel however they are a pointless extra expense.

They DO work but what has been said several times and seems to be ignored each time is, if the OE filter is more than up to filtering more air than can be used by a diesel engine then what is the point of spending more money (not to mention the fact you need to clean it) just to filter even more air that cannot be used??

I have used K&N filters with good effect on NA rally cars, on a diesel however they are a pointless extra expense.

So would the science be any more solid for the petrol 1.8TSi's out of interest? And any more advantageous to a remapped one? :wonder:

Aha! Now you're talking. If you up the fuel comsumption from standard, by whichever means, then you might also need to up the oxygen intake. So what may appear to be more is wasted, isn't.

Don't care if it works or not in theory.....see pic

Don't care if it works or not in theory.....see pic

Have you calibrated the MFD display though?

I can (and do) get 55+MPG (actual) on a 17K old OE filter, my MFD consumption was 10% optimistic, meaning the MFD display would of read over 60MPG too.

(In my Superb Combi 170CR)

Now if that is a calibrated (true) consumption and was on "consumption 2" then I would be impressed.

Have you calibrated the MFD display though?

I can (and do) get 55+MPG (actual) on a 17K old OE filter, my MFD consumption was 10% optimistic, meaning the MFD display would of read over 60MPG too.

(In my Superb Combi 170CR)

Now if that is a calibrated (true) consumption and was on "consumption 2" then I would be impressed.

So would I be! Power AND economy... the Holy Grail of the current motoring world.

Have you calibrated the MFD display though?

I can (and do) get 55+MPG (actual) on a 17K old OE filter, my MFD consumption was 10% optimistic, meaning the MFD display would of read over 60MPG too.

(In my Superb Combi 170CR)

Now if that is a calibrated (true) consumption and was on "consumption 2" then I would be impressed.

Pedant No 3's contribution coming up! ->

Presumably, since the speedometer on the Yeti is 8% to 10% optimistic (ie at an indicated 70mph, you are actually doing 65ish), then the milometer (odometer) is probably also reading high (ie you aren't actually going as far as the display shows). The Columbus SatNav seems to bear this out when comparing a journey over say 100 miles or so. For example, the Satnav predicts 100 miles, mileometer records around 110 miles on that journey.

So Gizmo if I interpret your post correctly, you have deduced that the fuel consumption display is normally showing an optimistic consumption figure which is why you have re-calibrated it - and that seems the logical thing to do. But, what distance do you calibrate it to? Actual distance covered using GPS over a flat surface of a considerable distance of 100+ miles, or have you assumed that the indicated mileage shown on the car's odometer is good enough? Ideally, without totally controlled conditions, any comparisons of MPG need to be made over several tanks full of fuel, as well as the same journey in the same climatic conditions.

I think we are opening a can of worms here! :S

Edited 31 December, 201114 yr by speedsport

Sorry Octygone, but a photo of one readout on the MFD doesn't prove anything. It also needs details of the actual miles travelled etc.

Sorry Octygone, but a photo of one readout on the MFD doesn't prove anything. It also needs details of the actual miles travelled etc.

12 miles old filter 53 or less mpg

K and n on same trip as per the pic

Both done on an the same uncalibrated readout and is constantly giving better mpg ....its.good.enough for me

12 miles old filter 53 or less mpg

K and n on same trip as per the pic

Both done on an the same uncalibrated readout and is constantly giving better mpg ....its.good.enough for me

I'm sorry, but saying that you are getting over a 10% improvement over just 12 miles just isn't statistically viable. You really need to take it over a much greater distance, such as per tankful.

I'm sorry, but saying that you are getting over a 10% improvement over just 12 miles just isn't statistically viable. You really need to take it over a much greater distance, such as per tankful.

+1 Agreed.

If I can motivate myself there are advanteges to use K&N, what is the benefit (except the price) to choose this (air filter only) instead of this (induction kit)?

Pedant No 2's contribution coming up! ->

Presumably, since the speedometer on the Yeti is 8% to 10% optimistic (ie at an indicated 70mph, you are actually doing 65ish), then the milometer (odometer) is probably also reading high (ie you aren't actually going as far as the display shows). The Columbus SatNav seems to bear this out when comparing a journey over say 100 miles or so. For example, the Satnav predicts 100 miles, mileometer records around 110 miles on that journey.

I think we are opening a can of worms here! :S

I agree with the speedo optimistic by about 10% and have used my satnav to determine what the exact corresponding km/hr are for the 70mph etc, eg a true 70m/hr=123km/hr. It is easier to set the cruise control to the more exact km/hr reading than the speedo dial.

However I find the odometer and the satmav distance prediction is spot on (to within 1/10mile in 100 miles!) and I often do trip s of 100+ miles. Presumably Skoda have built in a safety factor on the speedo reading but are more or less spot on with the odometer. The only reason it could be out is differnt tyres from the standard?

I have found the difference between odometer readings and speedo readings common across most cars nowadys. C & U Regs state that the speedo can read up to 10% over, but nothing under, so that can be built into the electronic circuitry of the speedo. The odo can take a direct reading.

I give up ...I am quite happy that my car is doing more mpg...I am not out to scientificaly prove it does or will do the same on anybody elses car ....I very very rarely fill my fuel tank as I dont like carrying extra weight for nothing, and I am certainly not putting an old blocked air filter back in to prove it.

I give up ...I am quite happy that my car is doing more mpg...I am not out to scientificaly prove it does or will do the same on anybody elses car ....I very very rarely fill my fuel tank as I dont like carrying extra weight for nothing, and I am certainly not putting an old blocked air filter back in to prove it.

Think about it.

If your car is hyperthetically averaging say 60mpg, in 12 miles it will have used ONE FIFTH of a gallon, or just about ONE LITRE of fuel. Do you really think that that amount proves anything?

No-one is saying we don't believe you, it's just that your "sample" is far, far, far too small to provide any tangible evidence. If the mileage had been 100 miles then it would give a better indication, and 400 miles would be better still. You say you never fill your tank up but you can still do a test with just the litreage to mileage comparison from the MFD.

And a proper test would have been between the K & N filter and a CLEAN normal filter, not the dirty on.

If I can motivate myself there are advanteges to use K&N, what is the benefit (except the price) to choose this (air filter only) instead of this (induction kit)?

The benefit of using the 57i Induction kit over an OE replacement filter is that you get even more air in through the filter, as you are dispensing with the OE airbox with its somewhat limiting airflow properties, and thus should get better power and/or fuel consumption.

However, beware that you are not leaving the airflow open to water spray/vapour that you really don't want.

Another aspect, as I found when I fitted a K&N 57i induction kit to my Octavia vRS TDI PD170 (remapped), was that whilst I got better top-end breathing and power, I lost out on low range torque. Ultimately I reverted to a replacement panel filter in the OE airbox.

That reminds me of my old Triumph Spitfire Mk3.

I replaced the engine, just a straight swap complete with gearbox, and the replacement had 11/2" SU carbs with a gauze & foam chrome air filter. Under load would not rev over 4000rpm. Spent ages trying to work out what problem was. Car had 4-2-1-2 exhaust fitted as well. Original engine had 1 1/4" SU carbs fitted.

In the end I put the standard airbox & filter from the old engine on and all problems disappeared. Too much air and not enough fuel.

The Spitfire was fantastic after that. Had a few handling & brake mods as well. Handled like no other mk3. Actually handled as well as a MK iv Spitfire.

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http://lyxus.net/irra was the best price I came across.

Ordered 6pm Boxing Day - arrived yesterday!

Just wondering if Merlinman had tried the K&N filter and noticed any improvement?

Yes and not really!

Less service cost in the long run?