Author Topic: My air filter DIY: £15 KN ebay cone & heatshield  (Read 2498 times)

Offline whileoceanasleeps

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My air filter DIY: £15 KN ebay cone & heatshield
« on: 21 September 2012, 22:46 »
Hey,

Did the air box mod to my stock green MK3 8v with the oem filter and after accidentally buying a BMW M3 K&N panel for it (anyone want it!?) i managed to get a K&N cone for £15 on ebay. Read a lot on here that using a panel and the air box mod is best but thought I'd have a go with the cone (for sounds also). However upon arrival I found no way to attach the cone to where my air box used to be, so here's what I did...

previous air box mod


was bring to work out how i was gonna make an 8" tube from bending some steel (pita) when i found an old lorry fuel filter that was the exact diameter of the cone! result


cut the ends off


stripped the paint with an air sander and made a bracket cut from 2mm steel sheet


bracket drilled to mount onto MAF and hole cut around a mug (very shakily!) with plasma cutter




The fuel filter was really tricky for me to weld at 0.5mm thick! I'm no expert welder, it kept blowing through. Helps to know a welder :) Not the neatest job but it stuck em together


main bit done! plus new gasket thing stanley knifed from some rubber mat


with filter


in the engine bay



took it for a test drive after this, i was curious to see what the heat soak would be like.. after a 5 minute trip round the block i opened the bonnet to find there was a lot of hot air getting to the filter. so i started making a heat shield...

a rusty couple of bits of 2mm steel cut and bent to fit around the cone..


a bit of the air sander to clean up the rust..


much easier for me to weld! note little nick out of the bottom to fit over wires in engine bay


finally in engine bay. the heat shield just drops in under the cone



have since sprayed with a quick lick of black fireproof stove paint! (helps to know a fireplace fitter!) a bit of running though, need to sand down and recoat.


all this cost me nothing over the price of the filter! admittedly i have access to a workshop :)

and there you go! not the cleanest one i've seen but it does the job for me and it was fun making :) the sound is way cooler than it was before, the car is stock except for a bigger exhaust the previous owner fitted. not too sure if it's any quicker, i think it might be but i may just be hoping!

checking the heat of the shield after a little driving i found it's heating a little, need to get some sort of insulation to cover it. went to wickes and a local hw store today but found nothing! if anyone knows a cheap way of insulating let me know!

thanks





Offline CJA321

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Re: My air filter DIY: £15 KN ebay cone & heatshield
« Reply #1 on: 21 September 2012, 23:27 »
Thats good work bud, nice1. I hate those hitachi MAF's

Offline whileoceanasleeps

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Re: My air filter DIY: £15 KN ebay cone & heatshield
« Reply #2 on: 21 September 2012, 23:38 »
thank man.

no idea what the alternative to the hitachi would have been, couldn't find any info. i'm still learning :)

Offline CJA321

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Re: My air filter DIY: £15 KN ebay cone & heatshield
« Reply #3 on: 22 September 2012, 00:00 »
Can get a k and n for them with a bracket like youv made. On ebay, quite expensive though

Offline tweed

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Re: My air filter DIY: £15 KN ebay cone & heatshield
« Reply #4 on: 22 September 2012, 00:02 »
They also sell a adaptor like you made but a lot shorter.

Untitled by tweedub, on Flickr

Offline brett

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Re: My air filter DIY: £15 KN ebay cone & heatshield
« Reply #5 on: 22 September 2012, 00:30 »
i had k & n filter with a mounting bracket etc .. in mine when i got it ,soon came out and replaced with standard airbox ,gave it to a bloke at work who reckons his cars loads better with it  :huh: