R

RobSimpson1951

New Member
Is it worthwhile fitting a K & N (or similar air filter)
What Size?
Remove induction trunking?
In the past I have had an element only fitted to my Vauxhall Senator 3.0 24v - long term it just saved on replacement elements & did not choke up.
I fitted a 3 inch high one on my '85 Ford Capri 2.0 Pinto - it released about 8 more BHP & a bit better fuel economy and also 'cos I removed all the induction trunking the induction roar sounded great
Rob
 
If all you want is more induction noise, there are probably cheaper ways of doing it.

K&N are over-priced and really don't do anything that the standard filter doesn't do already. The standard filter can pass considerably more airflow as it is, so unless you are shifting a lot more fuel and air, stay with the LR filter.

Before you say they can be washed out and re-used, once you've killed your MAF sensor with solvent traces you'll appreciate the standard filter more.

Peter
 
listerdiesel said:
If all you want is more induction noise, there are probably cheaper ways of doing it.

K&N are over-priced and really don't do anything that the standard filter doesn't do already. The standard filter can pass considerably more airflow as it is, so unless you are shifting a lot more fuel and air, stay with the LR filter.

Before you say they can be washed out and re-used, once you've killed your MAF sensor with solvent traces you'll appreciate the standard filter more.

Peter
Click to expand...

Very well said Peter, I totally agree with you. :cool::cool:
 
johnlad said:
i disagree, bhp goes up and throttle response is improved
Click to expand...

How?

Please quote the basis for your claim.

If the car is original and no adjustments have been made to fuelling, how does changing the air filter give you more power? & please don't say because it breathes better.

Peter
 
I have twin K&N's on my 110, but then I also have had the carbs jetted to match, a Piper H200 cam, and a more open exhaust. On their own the K&N's make very little difference, but they are important if you are planning to tune your engine for more performance.
 
listerdiesel said:
How?

Please quote the basis for your claim.

If the car is original and no adjustments have been made to fuelling, how does changing the air filter give you more power? & please don't say because it breathes better.

Peter
Click to expand...

i believe I already have, by stating that the throttle response improved and although i didnt rolling road the car, on many others ive fitted them to i have and seen bhp improvements, the car was more spritely
 
martin1512 said:
I have twin K&N's on my 110, but then I also have had the carbs jetted to match, a Piper H200 cam, and a more open exhaust. On their own the K&N's make very little difference, but they are important if you are planning to tune your engine for more performance.
Click to expand...

Agree, any filter mods without adapting the rest of the induction and even the exhaust system to match is pretty much pointless.
Had a bike to sort out once where previous owner fitted very shiny nice K & N filters and it ran like a bag of **** as still had standard jets fitted in the carbs and standard pipes, so stuck standard air filters back on and it ran far better...it was a two stroke motor though, very dependant on balanced system.
 
Well, that certainly brought some interesting replies! I had some data on rigorous back to back tests comparing brand new K & N's with brand new paper filters. They all flowed over 99%. The difference was the fact that the paper filter gradually blocked up & lost flow wheras even a blocked K &N still flowed over 99%. The only way to improve flow and BHP is to remove restrictions, usually the induction ducting. Depending on the layout this can lead to other problems (cold start problems, recirculation of exhaust gases etc.) K&N's rarely need cleaning, but when done it must be thorough & dried also
 
bushwwacker said:
Try breathing through a basic nuisance du
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Then try breathing through your shirt ...

Any difference?
Click to expand...

No one is saying that K&N's are not less restrictive than the normal air filter, it is just that on their own, make little difference. Unless the air filter is blocked, then it is not the filter that restricts the amount of air going into the engine, but the engine itself. The intake valve lift and duration are far more critical to the engines air intake, than the filter. If you fit a high lift, long duration cam, the engine can suck in air faster and for longer. This is when a performance filter can help, but that is not the end of the story. In order for petrol to burn properly it needs to be mixed with the right amount of oxygen, this is called the Stoichiometric ratio. Too much oxgen, and the fuel will detonate rather than burn, properly, reducing the engine's power, and even causing damage. So, if you increase the amount of air the engine takes in, you also have to increase the amount of fuel. On injected engines, this is controlled by the ECU, via the MAF and Lambda sensors. On a carb fed engine, this is done by adjusting the mixture setting on the carbs, and by fitting bigger jets.
But this still isn't going to make a huge difference to performance. The biggest restriction now is the exhaust. The air and fuel mixture can't get into the engine any faster than it leaves. Fitting the high lift/long duration cam will help with this, but there is still a lot of restriction in the exhaust. To overcome this, you need a free flowing sports exhaust and manifold. The faster the exhaust gasses leave the engine, the faster the new charge can enter. The air filter is such a small part of the engines induction and exhaust system, that simply changing that on it's own will have only a limited, if any effect at all.
 
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johnlad said:
i believe I already have, by stating that the throttle response improved and although i didnt rolling road the car, on many others ive fitted them to i have and seen bhp improvements, the car was more spritely
Click to expand...

If the vehicle wasn't put on the rollers then what else did you use to see your increase in BHP? nodoubt you also saw an increase in torque in the same crystal ball.
 
Well, thanks for the science lesson, good job I understand it all (what about bmep?)
But, back to the original question, has anyone fitted a K & N induction kit?
 
RobSimpson1951 said:
Well, thanks for the science lesson, good job I understand it all (what about bmep?)
But, back to the original question, has anyone fitted a K & N induction kit?
Click to expand...

Yes I have. But as I said earlier, I also have re-jetted carbs, a performance cam, and straight through exhaust. I fitted the K&N's first, but on their own, made very little difference over a brand new, standard, filter.
 
martin1512 said:
Yes I have. But as I said earlier, I also have re-jetted carbs, a performance cam, and straight through exhaust. I fitted the K&N's first, but on their own, made very little difference over a brand new, standard, filter.
Click to expand...

Done that with my 2.0 Pinto engine Capri, which is fitted with a ported head, piper 270/2 cam, Janspeed exhaust, Kenlow fan, electronic ignition and re-jetted Webber carb plus the K&N and all that produces 148bhp at the wheels so an increase of 52 BHPs on the Ford quoted 96 for this engine £500+ well spent. :D

The K&N gave me 1 BHP when it replaced the stock Ford filter and the Kenlow fan just 5.
 

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discool said:
Done that with my 2.0 Pinto engine Capri, which is fitted with a ported head, piper 270/2 cam, Janspeed exhaust, Kenlow fan, electronic ignition and re-jetted Webber carb plus the K&N and all that produces 148bhp at the wheels so an increase of 52 BHPs on the Ford quoted 96 for this engine £500+ well spent. :D

The K&N gave me 1 BHP when it replaced the stock Ford filter and the Kenlow fan just 5.
Click to expand...
My engine mods haven't made a huge difference to max bhp. It is running around 200 bhp, which is about 13 bhp more than a stock 3.9 with EFI. But the biggest difference is torque in the midrange. It now feels like a big diesel, but will keep pulling to around 5500 rpm. :)
 
yup torque is the important bit, I don't have to knock it out of top into 3rd to get any where now.
Diso is standard just as it left the factory but have had the rev limiter cut in once or twice.:)
 
Thats really good for the Pinto, the best I ever saw was a Group A RS2000 Rally Car (Raced by Chris Mellors in the late 80's) which knocked out 151BHP on their own Brake. I based all my mods on articles in Triple C and a book by David Vizard (did he do a book/articles on the Rover?) The block and head were skimmed, 3 angle valve seats & shortened valve stems. I had a full Janspeed System inc 4 Branch & the tallest K&N I could fit(The bonnet had to be lowered GENTLY) The carb was gas flowed (knife edged butterfies & spindles & rejetted - I chopped the choke spindle & removed the secondary butterfly) Using Vizards Figures I'm guessing at around 125BHP. Being a typical Yorky the exhaust was 2nd hand, & I rebuilt the engine myself. Including machining, bearings & gaskets etc It must have cost under £100.
Its been good to talk, keep in touch, I want to learn more about the Rover (but dont want to strip the motor! Ive got a Senator engine to rebuild & I'm getting too hold for this.
Cheers
Rob
 
I so wanted to comment but others have beaten me to it with sound advice. I'm not a fan of any oil impregnated filter on a car with a hot wire type sensor as oil mist from the filter can damage a MAF quite easily.... K&N seem to be trying to claim both ends of the stick as it were... better filtration AND better air flow... how? if it is better at filtering it is going to impose a greater restriction, either immediately or later when the dirt particles stick to the oil... if it allows greater air flow it will offer a decrease in filtration...
In my experience K&N actually clog quicker than a standard paper filter, this requires a cleaning kit, itsself usually much more than the cost of a standard paper filter...
 
Well

Been running round type k&n in my 3.5 disco for years

Both with MAF on 14cux and without on megasquirt

I didn't fit it for power (makes no difference is you run no filter at all) or for noise (these v8s don't really give out much induction note) but for filter performance and reuse ability

I spend a lot of time in and around water and wanted an oiled filter that was mesh reinforced so that it could handle getting wet and slowly pass water through, a paper filter goes to mush and gets sucked in tut th'engine

I wanted a filter that could stand up to sticks and stones getting sucked down the snorkel, a standard filter is ****, my k&n is years old and is great

Every few months I open up the box, take the filter out, dig all the sticks/leaves/mud/stones out of the box, brush/vac/blow the **** out of the filter and refit it good as new.

Will have saved me many many pounds by the time I'm done cos it'll last longer than the car.

Always ran paper filter in my Type R Honda cos the k&n didn't give any gains on the dyno and preferred to fit new paper every few months but for the landy it's he strength and durability of the k&n that makes it ideal :)
 
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