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K & N Cone Filter

Posted: Sun Jan 28, 2007 9:38 pm
by Deens
Anyone has any input regarding using cone filters. I bought a K & N cone filter as recommended by the man in the shop c/w adapter and servicing kit. I made a special bracket to mount it and sorted out a new home for the dropping resistor. A good afternoons work. I took the car for a spin and it ran like a dog. No power, holding back and very jerky. It also made a rattling noise when i took my foot off the accelerator to change gears. I had to take the filter off and revert back to the original. Does the engine now have to be tuned to accept this lovely filter? Very sad.

Posted: Mon Jan 29, 2007 12:34 am
by veecee
it shouldn't have such a dramatic effect on your car!

the rattling noise, what you mean???

when i installed mine, i could suddenly hear all sorts of things i couldn't before. things like suction noise as soon as you put your foot on the throttle, and the wastegate chatter when you let go of the throttle.

mine was in conjunction with a bigger exhaust, and it suddenly was popping and burbling on decel too.

so maybe more descrition is necessary, and are you absolutely sure that you can rule everything else out (other than the cone filter)???

Posted: Mon Jan 29, 2007 7:37 am
by ChemCool
it shouldn't have such a dramatic effect on your car!
I will lie if I could agree with the above. It has an effect. My car could not be dyna tuned at all!!!. It was either reverting back to stock filter, or unichip to change characteristics. I converted back to the stock filter. Today I have unichip fitted, but still with the old stock filter. Even if you dont experience any problems with your cone filter, it is always heat, heat, and more heat.

Posted: Mon Jan 29, 2007 9:58 am
by Gary57
How much did you pay for it and where from?? I am looking for a 76mm, best quote R400.00

Posted: Tue Jan 30, 2007 10:57 pm
by Deens
Gary, R400 I think is a good price. I know that you have a cone filter at the moment and it works...Does the heat not affect it? I mean do you feel a difference between when the engine is cold and when it's hot? How does one keep it away from heat inside the engine bay? I wonder if there is some sort of shielding required. I paid R755 for the filter, adapter, and servicing kit.

Posted: Wed Jan 31, 2007 6:40 am
by The Calibrator
A cone filtre hanging in your engine bay is a waste of money all you are doing is lowering the detonation threshhold of your motor by feeding it hot air.
Remember Nissan do not measure air temp or do any correction for it. You will be running the same timing and fuelling regardless of air temp.
Also no stupid little metal shield attached to your filter is going to stop it from sucking hot air.


If you really want a CAI then spend your money on a BMC CDA or equavalent

Posted: Wed Jan 31, 2007 9:12 am
by Gary57
Remember Nissan do not measure air temp or do any correction for it. You will be running the same timing and fuelling regardless of air temp.
The MASS AIR FLOW does compensate for heat. It measures the density of the which is dependant on the heat and altitude. You know how the MAF works so I wont explain.

I saw a heat shield pic of a sx once, it just made the cone filter have its own compartment, cant remember where. It looked real nice, it blocked off the whole area where the airbow used to be.

There is a slight difference when its hot i suppose, doesnt really bother me.

I think some one should put there car on the dyno with the airbox and then strip that out and put a cone, then we can see if there is really a difference. I personally dont think there will be, yes the cone takes more heat but the airbox is more of a restriction.

Maybe get some one to measure intake air temps and compare??

Posted: Wed Jan 31, 2007 9:22 am
by ChemCool
I think some one should put there car on the dyno with the airbox and then strip that out and put a cone, then we can see if there is really a difference.
Gary, I have done that. Dyno with, dyno without. No go. You can dyno it, but it was ness to fit unichip to compensate. Then I did measure temps right in front of stock air box. Sometimes up to 48 deg Celsius, and that inside the round pipe about 2 inches from box. Can you imagine heat in engine bay. Can post pic of temp sensor fitted. As far as I know, the cooler the air in the better. :roll: :roll:

Posted: Wed Jan 31, 2007 9:40 am
by Jay_boy
look guys as far as i can tell no matter what your air temp is your turbo is above 400C at operating temp and can go up as far as 900 so the air is gona get heated one way or the other, heat does not have such a big difference on force induction as on a normal aspirated car cos the pressure stays constant thanks to your waste gate :-) k snooby had the same quirk with his car all i did for him is clean his air flow sensor and bob's your aunty :-) try it and let me know? Cheers

Posted: Wed Jan 31, 2007 10:00 am
by Gary57
Sometimes up to 48 deg Celsius


Was that with the airbox in place?? What was the temp with the cone filter??
look guys as far as i can tell no matter what your air temp is your turbo is above 400C at operating temp and can go up as far as 900 so the air is gona get heated one way or the other, heat does not have such a big difference on force induction as on a normal aspirated car
Thats my way of thinking, besides if your cooler have a good enough effiency it will bring the charge temp down to ambient tempreture anyway.

If turbo intake temp made a huge difference surely the drag guys in the states and AUS would use a air box, but they dont they suck air from the turbo intake with no filter (they have too much money) which to me is the hottest place.

Posted: Wed Jan 31, 2007 10:10 am
by Dislex666
i wouldn't put too much value into what the drag guys do...

they don't build engines to last 100 000km

If their shit pops, they just gooi another one in

Posted: Wed Jan 31, 2007 10:18 am
by Gary57
But they are out there for power so they would be the ones to know what gives more.

Posted: Wed Jan 31, 2007 10:24 am
by Dislex666
yes - that's true.

That's why they DON'T have filters = FOKOL restriction.

So sschweet - i'm gonna can my air filter, cuz it's obviously not needed...

because the DRAG guys do it...


see? it'll be dumb - you _need_ a filter, it's not a 'maybe i should have it'. And sucking in colder air would mean it's denser, the turbo doesn't have to kill itself to make the same boost it would by sucking hot air.

And being at altitude your tubby is already taking strain to make the same boost it does down at the coast.

End of the day - if you can get colder air, no matter what induction you running (na/fi) you gonna benifit. Whether it's power or long term reliability

Posted: Wed Jan 31, 2007 10:37 am
by Gary57
Yes I agree with that but by having a airbox you are creating a restriction which the turbo has to do work harder to overcome, pretty much the same as it needs to work more becuase of the increased heat. But anyway your intercooler should be be bring the charge temp down to almost ambient temp.

I honestly dont believe that the intake temp being down by 10 or so degrees will have much of an effect once it has passed through the 600degree turbo and then through an intercooler.

Posted: Wed Jan 31, 2007 10:46 am
by Dislex666
i'm pretty sure it's much more than 10...

i mean, if it's 30 outside, it's gonna be like 50 inside the engine comp