Modifying stock airbox

[lawrencelyl]

Airflow of stock airbox is quite restricted. Thus, thinking of how to improve the airflow. Found out this website which basically modifying the stock airbox by removing all the pipings before the airbox and cut the airbox to make bigger hole for easier air suction.
URL: http://www.blytz.addr.com/howto/stockbox.html

I did mine similar to the website...
Result is lighter rev but noisier (sounds like open pod).
However, there're several issues for this mod:
1) Heat from engine (need proper heatshield).
2) Possibility of water entering air filter.
3) Noise (loud air suction sound).

FYI, i'm using stock Proton air filter and i'm not cutting my original airbox. Went to chop shop to get another airbox and cut it... i keep the original airbox :P

1st pic:

 

[lawrencelyl]

2nd pic:

 

[lawrencelyl]

3rd pic:

 

[EG9wannabe]

change standard paper filter with K&N .. better filteration ..

if yu afraid water to drip onto the filter .. cover the top part with sunshed .. bikin nice nice wan .. like I did mine ..

 

[szekeiemme]

check out edwards aka et5828.. is did sumthin like dat.. but his doesnt need cutting.. eheehhe check out de CAI thread

 

[lawrencelyl]

yeap... saw the pic of et5828 filter...
For my case, can't do like what he did coz no support on the air filter + the piping after the air filter. The airbox before the air filter is screwed to the car body to support both the air filter and the piping after the air filter. Hope you understand what i'm trying to say... hehe :P

 

[lawrencelyl]

Originally posted by EG9wannabe@Dec 30 2004, 15:03
change standard paper filter with K&N .. better filteration ..

if yu afraid water to drip onto the filter .. cover the top part with sunshed .. bikin nice nice wan .. like I did mine ..

wait until i have money to change to replacement air filter :P
later maybe will use SuperLon to do heatsheild...

 

[szekeiemme]

Originally posted by lawrencelyl@Dec 30 2004, 15:17
yeap... saw the pic of et5828 filter...
For my case, can't do like what he did coz no support on the air filter + the piping after the air filter. The airbox before the air filter is screwed to the car body to support both the air filter and the piping after the air filter. Hope you understand what i'm trying to say... hehe :P

yup.. i read 2 times den oni i understand.. ehehhee... er... if use K&N rite... its oil based... i scared de oil will dry out faster...

 

[lawrencelyl]

maybe the oil will dry out faster... but then can re-oil mar... :D

 

[drexchan]

is it possible to relocate the fuse box? If it's possible, then a bigger hose (3") can be used for CAI purpose. That will suppress the noise too.

 

[alantan]

another way is you don;t have to cut out..just drill some small holes...let say 6 holes?

that will also allow more air to go in already..

 

[drexchan]

i have got myself a role of 3" (or probably 3.5", need to confirm) flexi hose like those ninja sells. I am thinking or relocating the fuse box, re-frab the airbox to a bigger opening, and CAI it to the back of the right bumper (infront of the tire)... then seal any possible holes and gabs so that only air from the bumper grill can goes in...

 

[hann]

strange...everyone seems to think highly of K&N replacement filter. I have been using it for almost 2 years. I was sold to this product after reading from mags, listened to sales people with the "ping pong ball" demo. But I have not felt any improvement on the performance at all. Maybe need to see figures from dyno just to satisfy my curiosity. Probably open pod would be better.

my best result obtained from any mod is removal of cat ( 2nd gear can drag to 90kmh instead of 70+kmh in standard form).

another obvious result is with powerzone cam and extractor but the only drawback is the unstable idling. not sure whether due to siemens VDO or the cam.

this is just my personal view.

 

[drexchan]

yes, the most obvious improvement mod (and the cheapest too) is the removal of the catalytic converter. But i believe most of us here are either drying of idea after all the possible (and practical mods), or simply want to preserve the air quality for a longer period..

;)

 

[EG9wannabe]

Originally posted by hann@Dec 30 2004, 17:53
strange...everyone seems to think highly of K&N replacement filter. I have been using it for almost 2 years. I was sold to this product after reading from mags, listened to sales people with the "ping pong ball" demo. But I have not felt any improvement on the performance at all. Maybe need to see figures from dyno just to satisfy my curiosity. Probably open pod would be better.

my best result obtained from any mod is removal of cat ( 2nd gear can drag to 90kmh instead of 70+kmh in standard form).

another obvious result is with powerzone cam and extractor but the only drawback is the unstable idling. not sure whether due to siemens VDO or the cam.

this is just my personal view.

using K&N is to getting cleaner air into the intake .. if yu wanna get performance, get HKS air flow .. but hafa sacrifice on fuel consumption and dust ..

 

[drexchan]

For me, instead of cutting the airbox or drilling holes on it.. i will smoothen the inner surface first..

 

[lawrencelyl]

Originally posted by drexchan@Dec 30 2004, 16:11
is it possible to relocate the fuse box? If it's possible, then a bigger hose (3") can be used for CAI purpose. That will suppress the noise too.

i think it's quite hard to relocate the fuse box due to massive amounts of wire connecting to it...
this mod only useful for those don't want to do CAI connected to the fog lamp area :P
btw, i don't think drilling small holes will do much improvements coz the amount of air entering through the small holes is not much...
smoothen the inner surface of airbox also a good idea but then not so easy to do...maybe will try to do it when i free :D

 

[lawrencelyl]

Originally posted by hann@Dec 30 2004, 17:53
strange...everyone seems to think highly of K&N replacement filter. I have been using it for almost 2 years. I was sold to this product after reading from mags, listened to sales people with the "ping pong ball" demo. But I have not felt any improvement on the performance at all. Maybe need to see figures from dyno just to satisfy my curiosity. Probably open pod would be better.

my best result obtained from any mod is removal of cat ( 2nd gear can drag to 90kmh instead of 70+kmh in standard form).

another obvious result is with powerzone cam and extractor but the only drawback is the unstable idling. not sure whether due to siemens VDO or the cam.

this is just my personal view.

i will feel a bit guilty if i remove the cat...haha...don't flame me for that :lol:
btw, my car in pure stock condition before all these minor mods also can reach 90km/h in 2nd gear...around 6500rpm :P
engine screaming like hell...still can go faster but don't dare to rev anymore...

 

[drexchan]

yes, i wouldn't suggest a cat removal. I have changed my S-flow end-muffler to the SE straight-flow. But center box and 4-1 extractor remain stock (normal sedan). The sound is slightly louder, more bassy and the ecceleration is much better, top-end improved as well. I guess that's all i'll do to my GLi at the exhaust system.

But intake.. hehe!! i'll definitely smoothening the inner surface or the box, TRY to relocate the fuse box, and then re-hole the airbox to fit-in a 3" or 3.5" flexi hose.... and so and so... Giant CAI.. hehe!!! So far using the K&N drop-in.. with the front U-shape snockle removed, not bad.. sounds garang too...

 

[szekeiemme]

another obvious result is with powerzone cam and extractor but the only drawback is the unstable idling. not sure whether due to siemens VDO or the cam.

unstable idling?? high cam ? high lo high lo high lo.. ah?