Mod to stock airbox - e46

[zennie]

Hi guys,

Just to share with you my little mod. I bought myself a cyberspeed air filter and after half a day, I went back to the workshop to uninstall it. The low end suffered, while the mid and high end made little to no difference. I even connected the end to the piping by cutting a hole in the stock Mtech 2 brake duct, so that air from beside the foglight goes to the filter thru the hole at the front of the LHF fender.

I removed the cyberspeed and decided to mod my stock intake box. I dug a 3" hole at the front of the air box, just right beside the flat hole that draws in air from the side of the radiator. I connected this 3" hole to a pipe which eventually leads to the LHF brake ducts at the side of the foglights of the mtech 2 bumper.

Result? Better low, mid, high. There is very little restriction as almost double the amount of air can come in easily and best of all is that it is cool air. There is some effect of ram air as well. Of course this setup would mean that you'll benefit more from a panel replacement filter. The 3" hole is cut using a machine at the workshop which cut a perfect 3" hole, which can fit a rubber 90 degree pipe, then from there you can connect a regular flex pipe to bring in fresh cool air.

Sorry, no pics now....but just to share with you all on this. I don't believe in open pods for auto cars. Can't sacrifice low end.

 

[sszone]

Re: Mod to stock airbox - e46

good effort bro, like u i crave for more cool air.
i tried the piping method b4, u will start to hiam after a while....hehe
u can consider the air charger thing if u want better low end.
filter wise, open pod are quite good for mid to high end, the only prob is that our cars are too hot....so its practically breathing in hot air
i am currently using a hks megaflow filter.
i also got a project in mind for lotsa cold air, just that have to do more planning and save up for it, will post that up when i finally get to it.
thanks for sharing your experience....it sures feels good knowing more ppl who are hands-on with their rides
1 more thing, u can try fitting in a bigger box if u better results

 

[zennie]

Re: Mod to stock airbox - e46

Bro,

I tried all sorts of intake on my Euro R (previous ride). Gruppe M, cold air intake (like those injen type) with longer runners, removal of resonators (jap cars have intake resonators which bimmers don't seem to have which gives the low end but is quite restrictive at high end). I even dynoed different intakes, etc.

If mine was a manual, I'd definitely run an open pod if you can somehow get fresh air, either thru a very efficient heat shield or thru a long intake pipe. I prefer a longer intake pipe because I noticed that you'd get more mid range torque with longer runners. Short rams are very good for high end but mid range sucks. There is never a BEST intake, but there is an ideal intake for every purpose. If I am running on aftermarket cams and manual, I'd definitely run on the shortest ram air with a heat shield. If it is stock cams that do not need that very high end, then I'd make the runners longer for better torque.

Now since I have an auto, I don't have much of a choice but to keep the stock airbox, which really does flow well compared to other cars. The mid and high is pretty acceptable especially after the 3" hole is dug into the box. I think the size is pretty decent as well. Overall, am very happy with this and seriously doubt if any other intake would give me overall driveability like this which providing better torque throughout the entire RPM range. I was so put off by the carbon intake because it wasn't even a case of sacrificing some low end for better high end. It was more of a case of sacrificing low end, for getting a bit more noise.

It's always fun to try and find out what works best for yourself. Cheers.

 

[sszone]

Re: Mod to stock airbox - e46

already dumped my carbon intake, my simota open pod....not what i wanted from em. kudos for having the courage to cut the 3" hole, not everyone dare to tinker with their rides....i know some ppl who dun even dare to open their bonnets, i was one of em in the past....haha.

 

[TripleM]

Re: Mod to stock airbox - e46

stock box is still the best, just ensure u get after mkt filter like K&N or Streamline Engineering drop in filters...work sweet

 

[zennie]

Re: Mod to stock airbox - e46

I saw my friend's e36 but didn't notice that a 3" hole can be cut but at least for the e46, I can nicely cut a 3" hole. Even if you can't do a 3" hole, even a 2" hole will make a good improvement. The only worry was a slight loss of low end but surprisingly there is no loss at all. Noise is not affected, just the extra torque. It's always good to find a mod that works, but of course this is not always the case. I had to spend $120 to buy the cyberspeed filter and then realizing it doesn't work well. But if I didn't the the cyberspeed, I wouldn't have thought of modding the stock air box! I missed up the cyberspeed cos i cut the fake carbon cover so that a 4" pipe covers the front of the carbon box instead of the 2.5", thinking that it'll help but yet it sucks, literally. But at least the end result was much better than stock.

By the way, a week later I also removed the idle control valve and cleaned it. Asked the mech to remove the throttle body and I ported (DIY at the workshop cos too troublesome to explain how I want it done) about ~2mm from the throttle body's inlet. I noticed BMW's throttle body's inlet/outlet is SO THICK. It is about 3mm thick while those japanese cars like civic/euro R ones are half as thick. I used a grinding tool (air powered, with the sand paper grinder head) to port and remove the throttle body's lip so that the end result is a funnel shaped (more like venturi lip) throttle body. I think this Spoon TB or other brands also do that to their TBs. Tapered but of course i didn't touch the surface area of the TB at the butterfly valve, which I know could cause problems with idling as there would be a gap at 0% throttle. Just so that when air enters the throttle body, there won't be the 3mm thick lip to produce turbulence. The volume of air should remain the same, but at least the speed going in can be increased with less turbulence. I have done it on my 2 previous cars with pretty good results, and noticed the same on the e46. Better throttle response, and feel that the torque gets built up quicker. Fun and rewarding.

 

[sszone]

Re: Mod to stock airbox - e46

hard to cut a hole in E36, thats why i told ya i have alternative plans for inducting more cool air....i guess we have to do trial n error on making modifications, like your cyberspeed filter....just like the stupid mirror i ordered from US lying in my storeroom which could not fit my ride...hehe

 

[xuexun]

Re: Mod to stock airbox - e46

I remember Ryan(Admin) did this before too. With pics and all.. Dunno where is the thread already though.

 

[zennie]

Re: Mod to stock airbox - e46

This is a pic of the air box, with the pipe on the left which leads to the bottom of the left fender.

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Stock throttle body

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Ported

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