Whilst getting some stuff sorted for my other car i decided to put my PD VRS on the dyno yesterday

Stock car with 60,000 miles only mod is a K&N filter element , no remap or tuning box

Surprised me a little

Nice result!

But I'm sure someone will come along and say "optimistic rolling road" etc etc

Nice result!

But I'm sure someone will come along and say "optimistic rolling road" etc etc

I'm sure they will but it was only calibrated the day before and checked that morning

Are you sure it wasn't mapped when you got it ?

Nearly 30bhp from a K & N filter is awesome otherwise - where can I get one ?

(No need to answer - I have one already, and a remap on my CR, so I should be running about 230bhp )

Are you sure it wasn't mapped when you got it ?

Nearly 30bhp from a K & N filter is awesome otherwise - where can I get one ?

(No need to answer - I have one already, and a remap on my CR, so I should be running about 230bhp )

Nope had the car four years it was a pre reg , i have heard that even stock ones would do mid 180hp on the dyno but didnt bother with the Octy as its a workhorse not interested with the power from it so only dyno'ed it as i was there anyhow so perhaps the filter only adds 10hp or so over stock who knows ??

I can say however it was noticably quicker and picked up 3 mpg according to the maxidot after fitting . The filter i replaced was a genuine one and had only covered 1500 miles so wasnt dirty , the k&n is a bout a 1/4 of the depth of the stock one though so you can see where any gains come from.

I will also add that this car has always felt strong it was run in properly ie spanked from new and feels a lot lot quicker than my CR 170 Superb

Nope had the car four years it was a pre reg , i have heard that even stock ones would do mid 180hp on the dyno but didnt bother with the Octy as its a workhorse not interested with the power from it so only dyno'ed it as i was there anyhow so perhaps the filter only adds 10hp or so over stock who knows ??

I can say however it was noticably quicker and picked up 3 mpg according to the maxidot after fitting . The filter i replaced was a genuine one and had only covered 1500 miles so wasnt dirty , the k&n is a bout a 1/4 of the depth of the stock one though so you can see where any gains come from.

I will also add that this car has always felt strong it was run in properly ie spanked from new and feels a lot lot quicker than my CR 170 Superb

I don't mean to be the party pooper but I would definately go to another dyno! Even if the 170 engine was producing a bit more standard there'sno way you'd gain that much from a filter, especially not on a diesel :wonder:

I have justp put a K&N panel filter in my new TSI vRS and I dont think its made any difference, I just put it in ready for my remap next week

I don't mean to be the party pooper but I would definately go to another dyno! Even if the 170 engine was producing a bit more standard there'sno way you'd gain that much from a filter, especially not on a diesel :wonder:

I have justp put a K&N panel filter in my new TSI vRS and I dont think its made any difference, I just put it in ready for my remap next week

I dont think i'll bother i have a Lancer with 370hp so i'm not chasing a few hp on the Octy , just thought some people would find it interesting , seems not

As for filter gains i have found "in my personal experience" that diesels in general (not just Skodas) are very sensitive to air filters far more than petrols, I could feel performance dropping off on my last car Merc E class 320 CDI when the air filter got to around 10,000 miles despite the service interval being a lot longer than that , the fitting of a K&N stops this as there is no noticable perfornance drop off at that mileage and i only bother cleaning them every 2 years of so. The fact the fuel economy has gone up a great deal also indicates to me that the engine is more efficient

Problem with dynos is that you take the same car to five dyno's you get five different results the biggest joke of all is the before and after results some tuners provide , its in their interest to show dramatic gains and dyno figures are childs play to fudge, I use two dynos for my cars this one and another for 4wd cars and neither tune my car

I will also add that this car has always felt strong it was run in properly ie spanked from new

can someone explain this to me please?

I've always been under the impression that "running a car in" means you don't spank it until about 3k miles?

then I also hear people saying "modern cars are so well built they don't need running in"

which is it? :S

TIA

Edited 13 June, 201016 yr by Herschel

Air filter will make virtually no different on a Diesel engine. Power is controlled in a diesel by fuel metering, not air metering, up to the point where there is more fuel than the unthrottled airflow can use, ie excessive black smoke. Diesels are inherently 'lean burning' engines so unless the filter is really choked with muck its all placebo. There might be a tiny, almost immeasurable, gain due to reduction in pumping losses across the filter.

The idea that modern engines don't need running in or benefit from being run hard during the break-in phase is part of modern motoring mythology. Many manufacturers use a different spec oil for the factory fill to promote running in and piston-bore seating. A few others (e.g. Subaru) still specify a 1000mile oil change to eliminate the swarf which accumulates in the oil during the first miles of running.

Edited 13 June, 201016 yr by Hauptmann

Are you sure it wasn't mapped when you got it ?

Nearly 30bhp from a K & N filter is awesome otherwise - where can I get one ?

(No need to answer - I have one already, and a remap on my CR, so I should be running about 230bhp )

The K&N will have added nothing to the result.

Most of the PD140 put out about 170bhp at JKM, so it wouldn't surprise me to see a PD170 close to 200bhp.

perhaps the filter only adds 10hp or so over stock who knows ??

: Mmmm, magic filter

Air filter will make virtually no different on a Diesel engine. Power is controlled in a diesel by fuel metering, not air metering, up to the point where there is more fuel than the unthrottled airflow can use, ie excessive black smoke. Diesels are inherently 'lean burning' engines so unless the filter is really choked with muck its all placebo. There might be a tiny, almost immeasurable, gain due to reduction in pumping losses across the filter.

The idea that modern engines don't need running in or benefit from being run hard during the break-in phase is part of modern motoring mythology. Many manufacturers use a different spec oil for the factory fill to promote running in and piston-bore seating. A few others (e.g. Subaru) still specify a 1000mile oil change to eliminate the swarf which accumulates in the oil during the first miles of running.

Mmm perhaps but I do know prior to the filter being changed at around 55,000 miles the car was very very slow , my wife had been driving it and hadnt noticed but pulling off the lights it was dog slow wouldnt even spin the wheels in 1st gear , clearly the air filter had had enough and needed a new one but if airflow isnt important on a diesel why do they have a MAF??

Whether the K&N filter adds any power or not I dont know what i do know is the car drives better off boost and has picked up 3mpg on average since fitting it and the other week the mfd showed 50mpg on a motorway drive and in the 4 years and 60k of having it the best i have ever got was 48mpg , this also tallies with my experience of fitting one on my E320 CDI some years ago

Air filter will make virtually no different on a Diesel engine....... There might be a tiny, almost immeasurable, gain due to reduction in pumping losses across the filter

I can strongly confirm this statement. Five years ago I have conducted extensive tuning project for major national car magazine using 2.0 90HP PSA diesel engine. Following mods were done: chip tuning, K&N filter replacement, exhaust swap and intercooler addition. All the mods were done one at the time and every stage was measured for torque and power using Danish road dyno system.

Among all the mods made filter swap produced by far the smallest power gain. Actually, power curve deviation just started to occur at 4000 rpm where diesel engine started to give up. Power gain was in the order of 1% as I can recall now. We have concluded that petrol engines with much higher revs could probably gain much more with such filters.

Interestingly enough, filter mod produced some 3 db more noise both inside and outside the car!