Performance air filters

I'm thinking of using a non standard air filter on my 1.8 K series (reusable type pos)

I've got a universal cone filter that I used on my petrol vectra, but the engine bay on my fl seems to get a lot warmer, ive got a few pipes/tubes and make shift heat shields I could use to overcome this and to get cool air to the filter... Any thoughts/advice would be welcomed

Or do I use the panel type in the air box...K&N etc

Anyone used the britpart performance air filter?

A simple cone filter in the engine bay is worth nothing where power is concerned. It makes more noise and nothing else.
You need an enclosed high flow air filter picking up cool air from outside the engine bay. There is a 70mm hole on the LH inner wing, right below the headlight that is an ideal cold air pickup point.
A pleated cotton filter in the standard box will flow less air than its paper counterpart!!

Nodge68 said:

A simple cone filter in the engine bay is worth nothing where power is concerned. It makes more noise and nothing else.
You need an enclosed high flow air filter picking up cool air from outside the engine bay. There is a 70mm hole on the LH inner wing, right below the headlight that is an ideal cold air pickup point.
A pleated cotton filter in the standard box will flow less air than its paper counterpart!!

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I'm not after any power increase just better air flow...excuse my dumbness are you saying an after market performance filter or standard replacement?

It is a good idea, using a K & N filter, high quality,but for the increased performance would be needed an evacuation route and custom made without catalyst and a larger diameter pipe for the flowing easier

sparkysbandit said:

I'm not after any power increase just better air flow...excuse my dumbness are you saying an after market performance filter or standard replacement?

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Why are you looking for better air flow without any power increase? The engine will only breath what it can use.
The standard paper filter is more than up to the task of a standard or modified K series engine. The Freelander standard filter is the same size as the VVC MGF filter. On the VVC engine, it flows enough air to produce over 150 bhp. Paper is also better at filtering fine particles more efficiently. A "Correctly oiled" K&N does pass slightly more air, at the expense of dirt retention, ie it will pass larger particles than paper. A paper filter replaced at 12K mile intervals will still give acceptable results in the standard casing provided a cold feed is employed, and you can pick up a couple of bhp.

Thanks for the info/advice guys.
I change my filter once a year and clean it as and when with the hoover but don't tell her in doors
I just thought an after market filter may be more cost effective and as a bonus gain some better quality air?
Like i said I'm not that into gaining power, but when I had the cone filter on my vectra it did get up hills easier and picked up a bit quicker.
I have a straight through sport box fitted and it seems to have made it a bit ERM snappier...so if a better filter could save money and as a bonus give me a better throttle response then that's all good but not the be all and end all.

This argument is as old as the Internet. "K&N is worth it,..... or stock"? "Cold air intake,.....or not"?

MY experience: K&N is a RACKET. NO measurable benefits. I had them on MANY cars (maybe 20+). It does NOT do what it claims to do, and the "horsepower increase" is rubbish. If anything,....it lets MORE dirt into the intake.

True "cold air intake" WILL help, .....however, MOST of the "packages" offered on the web, are NOT what they claim to be. Modding the intake is a great way of providing the intake with what it needs, but some SERIOUS modifications to the engine bay are needed, in order to achieve this.

If one thinks the "kits" sold on Ebay will improve the performance, one is sadly mistaken. And the K&N in the stock airbox is a JOKE. The particle retention of the K&N is LESS than the stock paper filter! (don't take my word for it, and do your own research!).

I am sticking with the STOCK paper filtration on all my current vehicles, after I tried K&N, and numerous other "cold air intakes" from the "performance" shops.

You are welcome to your own conclusions.

Danielsand said:

This argument is as old as the Internet. "K&N is worth it,..... or stock"? "Cold air intake,.....or not"?

MY experience: K&N is a RACKET. NO measurable benefits. I had them on MANY cars (maybe 20+). It does NOT do what it claims to do, and the "horsepower increase" is rubbish. If anything,....it lets MORE dirt into the intake.

True "cold air intake" WILL help, .....however, MOST of the "packages" offered on the web, are NOT what they claim to be. Modding the intake is a great way of providing the intake with what it needs, but some SERIOUS modifications to the engine bay are needed, in order to achieve this.

If one thinks the "kits" sold on Ebay will improve the performance, one is sadly mistaken. And the K&N in the stock airbox is a JOKE. The particle retention of the K&N is LESS than the stock paper filter! (don't take my word for it, and do your own research!).

I am sticking with the STOCK paper filtration on all my current vehicles, after I tried K&N, and numerous other "cold air intakes" from the "performance" shops.

You are welcome to your own conclusions.

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Food for thought dude.

Yeah but a cone filter sounds much better than that nasty ol plastic standard noise killing box!

Danielsand said:

This argument is as old as the Internet. "K&N is worth it,..... or stock"? "Cold air intake,.....or not"?

MY experience: K&N is a RACKET. NO measurable benefits. I had them on MANY cars (maybe 20+). It does NOT do what it claims to do, and the "horsepower increase" is rubbish. If anything,....it lets MORE dirt into the intake.

True "cold air intake" WILL help, .....however, MOST of the "packages" offered on the web, are NOT what they claim to be. Modding the intake is a great way of providing the intake with what it needs, but some SERIOUS modifications to the engine bay are needed, in order to achieve this.

If one thinks the "kits" sold on Ebay will improve the performance, one is sadly mistaken. And the K&N in the stock airbox is a JOKE. The particle retention of the K&N is LESS than the stock paper filter! (don't take my word for it, and do your own research!).

I am sticking with the STOCK paper filtration on all my current vehicles, after I tried K&N, and numerous other "cold air intakes" from the "performance" shops.

You are welcome to your own conclusions.

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I disagree with you.

A filter different filter medium can pass more airflow over it. Be it foam, or wire mesh etc etc. However they need to be carefully oiled with the correct oil. Not spraying them with WD40 and going "that'll do".

It need not have a larger surface area to flow more air if it is less restrictive.

Installing an improved filter though will only give any power benefits if a) the original manufacturer was a twonk and just used the wrong filter (unlikely) or b) additional engine tuning is carried out in order to make use of the additional airflow which will become available due to less restriction.

The additional benefits of different filters are of course that they can be cleaned and recycled again and again. Potentially saving alot of money. I am forever helping my mate with his race car and he has to clean his foam filter after everyrace due to the dust. Cost - chuff all

If you live in a dusty environment then this could save you some money in the long run.


Now a cold air intake is something completely different to just bolting in a performance filter,

obviously a manufacturers have to build a vehicle which is usable by ALL people. including those who are inept. As such the air intake system must take into account typhoon conditions, people driving through deep puddles at high speed, various temperature differences, people expecting to use it in heavy snow..etc etc.

An off the shelf vehicle must cater for these eventualities and as such it is a compromise on all fronts. Yes an exposed cold air intake mounted away from the body of the car can offer significant gains in engine power, but it sacrifices in other areas previously mentioned.

vilguy said:

I disagree with you.

A filter different filter medium can pass more airflow over it. Be it foam, or wire mesh etc etc. However they need to be carefully oiled with the correct oil. Not spraying them with WD40 and going "that'll do".

It need not have a larger surface area to flow more air if it is less restrictive.

Installing an improved filter though will only give any power benefits if a) the original manufacturer was a twonk and just used the wrong filter (unlikely) or b) additional engine tuning is carried out in order to make use of the additional airflow which will become available due to less restriction.

The additional benefits of different filters are of course that they can be cleaned and recycled again and again. Potentially saving alot of money. I am forever helping my mate with his race car and he has to clean his foam filter after everyrace due to the dust. Cost - chuff all

If you live in a dusty environment then this could save you some money in the long run.


Now a cold air intake is something completely different to just bolting in a performance filter,

obviously a manufacturers have to build a vehicle which is usable by ALL people. including those who are inept. As such the air intake system must take into account typhoon conditions, people driving through deep puddles at high speed, various temperature differences, people expecting to use it in heavy snow..etc etc.

An off the shelf vehicle must cater for these eventualities and as such it is a compromise on all fronts. Yes an exposed cold air intake mounted away from the body of the car can offer significant gains in engine power, but it sacrifices in other areas previously mentioned.

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You are right in the statement that "off the shelf vehicle must cater for all eventualities". There is definitely room for "improvement" in MANY areas. I also appreciate that you disagree with MY experience with KN (and other) "performance" filters. But we are not talking about "performance/race cars" here. We are talking about "off the shelf", everyday rides, like the Hippo. The only thing I noticed in using these filters on my everyday rides, is more noise. Since a LOT of people put noisy exhausts, noisy filters, and other gadgets that change the audio signature of the vehicle, they must be thinking that "more noise = more performance". Sometimes it does, but mostly not.

I am especially peeved with numerous "cold air intake kits", that are nothing but a ripoff. There are ways to boost the horsepower on ANY engine, and it comes with a hefty price tag,.....in performance parts, labor, lower gas mileage, and premature wear on some components. All the "resistors", "cold air intakes", "performance filters" etc, are out there to make the kids think that couple hundred bucks will transform their mundane ride, into a fire breathing monster. Billions are made this way every year.

Since I was a dealer, I've seen so many cars where the stock air intake (e.g. designed to suck air from the fender), is tossed away for a Chinese made (shiny chrome tube!) "cold air intake" that has the metal tube, and the colorfull cone filter, positioned right over the hotest part of the engine, and sucks the air from under the hood! That's NOT a "cold air intake", just the opposite.

Now if the subject is ANY performance filters,.... the first thing that came to MY mind was K&N in the standard airbox. I think the ONLY "benefit" of that setup, is not buying new paper filters again, and that's a doubious benefit too. Like you mentioned,....."spraying WD40" on it is NOT going to work! And MOST kids do just that. Properly cleaning/lubing K&N is a MUST, but the "inceased airflow" that this filter produces in the stock airbox is negligent. Not sufficient enough to produce any more "power". If it's not washed/lubed properly, it actually becomes more restrictive, and the particles that were trapped in the foam may end up in the cylinders, next time around.

Anyway,.....everyone works for their money, and everyone is entitled to spend it any which way he/she wants. I only offered my opinion on the subject, and I stick to manufacturer recommended paper filters since the last "performance filter" I had on my last Hummer.

There is plenty of info on the web about the adverse effects of oiled K&N filters, they can damage the MAF. Unless you are into tuning the engine, the standard filter is more than up to the job.

Datatek said:

There is plenty of info on the web about the adverse effects of oiled K&N filters, they can damage the MAF. Unless you are into tuning the engine, the standard filter is more than up to the job.

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And THIS, about sumarizes it all.

Datatek said:

There is plenty of info on the web about the adverse effects of oiled K&N filters, they can damage the MAF. Unless you are into tuning the engine, the standard filter is more than up to the job.

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In this instance you are quite correct, although the 1.8 K series doesn't have a MAF to worry about.
Even a modified K series can use the standard air filter and housing. Like I said, with a suitable cold air pickup, the standard filter will flow enough air for a 150 Bhp VVC engine. Unless someone porting and longer duration cams are fitted, the Freelander K series doesn't get close to that sort of power.

Years ago when I ran a heavily tuned Triumph Spitfire. For a while used K&N filters on the carbs. After 500 miles you could feel fine grit on the SU carburettor piston. This grit as a mix of oil off the filter and road grit that had "passed" through the filter material it's self. Not good at all. It doesn't take a genius to work out what the long term damage would be caused to the valves, rings, piston and bores. Obviously I did away with the K&N filters and fitted large paper filters instead.
Imho go with paper, that's why manufacturers use it. It works.

Datatek said:

There is plenty of info on the web about the adverse effects of oiled K&N filters, they can damage the MAF. Unless you are into tuning the engine, the standard filter is more than up to the job.

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Plus 1 on that.

Carrington224 said:

Plus 1 on that.

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plus another 1 that makes 2

I was going to put a filter in mine but decided against it but I did knock the car out and I must say it's lot more poky now and my Ronbox has t even been fitted yet lol

As I tried to explain my convictions on this,.......general public IS deeply divided on the issue of "performance air filters". People that actually got their hands greasy, and saw first hand the differences between the cars using stock filters, and the ones using "aftermaket, performance" ones, KNOW which way to go.

And as long as we understand that we are talking about stock, everyday cars (NOT highly tuned/racing/drag etc. machines), people that have hands on experience, stick with paper, and as close to stock as possible.

I had a Triumph spitfire mk3 a few decades ago too.

I was given a new engine with 1 1/2" SU carbs in place of the 1 1/4" SU's fitted as standard. I had a 4-2-1-2 exhaust fitted as well.

The car had a problem. Under no load it would rev to the red line, but under load it would not rev over 4000rpm.

Eventually I realised that the mixture was too lean. The previous owner of the engine had fitted one of those chrome and gauze filters. I replaced it with the paper one from my old engine, and bingo. Everything was well with the world (and my spitfire).

There is a moral there somewhere.

Hmm, very topical! I use a K&N panel in my R25 and will fit a K&N pod to my FL1.

I'm in the process of getting my FL1 1.8 going. I'm taking the opportunity to do some mod's: I've deburred the plastic inlet manifold and checked the port sizes [ the plastic is slightly smaller than the alloy inlet side],
enshrouded the valve area in the head [both inlet & exhaust], and trimmed a wee bit [ 'back cut' ] off each valve to aid air flow,
The port's runners have been opened up a bit - maybe a couple of mm,
Trimmed any protruding valve seat bases to make a smoother air path and made an 'eased' the radius in each throat where there is a straight machined faces [ most noticeable on the short radius side of the throats],
Carved a bit out either side of the valve guide boss in each throat and trimmed of the valve guide itself [ shortened it a bit and rounded it off],
Port matched the exhaust side and removed any protruding lips or sharp edges and weld splatter right back to the first muffler,
fitted a decat pipe and will fit a K&N Apollo filter with a CAF from inside the front left guard [its end point just begs for a snorkel extension through the guard and up the LH A pillar - can anyone comment on that?]

My next plan is to explore what can be achieved by careful att'n to valve timing but without buying those expensive Verner pulleys.

My aim is to have a free breathing 'torquey' motor. I may gain some power and hopefully better MPG. Will let you know how it all goes.