My modified airbox!... (56k warning!) NOW with log results!...

[Avant4me]

Of course it improves when installing cold air induction, I wasn't arguing that.

I was trying to explain that for airflow, enlarging the size of tubing would not matter,
once it exceeds the size of the intake tube / manifold.

Just simply try to visualize it in your mind, by removing everything in front of the MAF (air filter/tubing) ... or even the manifold.

Now THAT HOLE is your airflow.

Then start visualizing holding an enormous tube - 10 miles wide - to that hole.
It doesn't matter, you see ?

This is true only for stattic air. The air in an engine bay is anything but stattic. The volume of air in a 100mm section of pipe is greater than that of an 80mm pipe of the same length. Once you then factor in the fact that air starts to be pushed into the intake simply by the movement of the car, you are starting to increase the pressure.
Since the turbo works by sucking air through the air filter normally, if you then increase the pressure on the other side of the filter (larger intake duct) then you are starting to overcome some of the vacuum. In short the air then travells into the MAF at a greater rate as it is now not just being sucked in, but also pushed in by atmospheric pressure as well.

It is exactly how RAM-Air works on motorcycles and how the manufactures quote such high power figures. a 2008 yamaha R1 makes a genuine 160 ish bhp, but with RAM air (they test in wind tunnels to reflect the speed of the bike at that engine speed) the quoted output is over 180bhp.

 

[D.K]

So would it be worth fiting a 100mm feed pipe made if silicone rather than a 100mm corrugated one ???

 

[Willie]

Yup smoother air flow
But remember air (gas) can be compressed so a slightly bigger diameter air supply will benifit you
I don't think you could get a too big diameter hose supply. It will never harm you

 

[HallycupraR]

end of the day ur supplying more cold air than is needed but aint that the point to keep it cold so in my eyes the bigger the better ?

 

[DPJ]

But at the end of the day, a big mofo open cone filter is the least resistance. If you've got an efficient intercooler that's your route to maximising power.

 

[Feel]

So would it be worth fiting a 100mm feed pipe made if silicone rather than a 100mm corrugated one ???

I wouldn't say it was worth it. Silicon + connectors would be a lot of dosh and a lot of faff, the difference in volume of air on a smooth bore vs. corrugated for the same size would be negligable in this application, especially as it then goes through a filter.

Probably better to go for larger than 80mm corrugated instead of 80mm silicon, I would've said.

 

[J@mes]

Hi, just read most of the post and its great stuff to see what you've done. Just to clarify did you find the best place for the hose to end at just before the headlight to the side of the battery? and where/how much was your hosing?
Cheers
Adam

yes I do believe the best position for the air feed is between the wing and battery without doubt! this is how mine now looks...

 

[cruising03uk]

so has everyone just fitted the intake pipe cold air feed just to the back of the healight now an not to front grill to get rid of bends and not to bottom of car as no way you can get it down there?

i am leaving in my original air intake from front grill and putting a big pipe between the battery and wing but only as far as a few inches behind the headlamp and should i leave in all the headlamp coverings or remove them for better greater air flow?

 

[cruising03uk]

LCR by the way ibiza is gone.

 

[Willie]

I wouldn't remove the head lamp back as this along will not improve the air flow significantly

Best bet is to fit a FMIC which frees up the space where the SMIC's were

 

[D.K]

Mine is the same as J@mes'
I removed the the black plastic cover that's ment to feed air to the filter and all the bracket's that hold it in place

FMIC would be good but very expensive.

 

[J@mes]

even with a FMIC it will still be VERY hard to run a decent feed to the fog light area. IMHO it is not worth the hassle (especially as it would be a narrow feed with lots of kinks!)

 

[jaybeee]

Holy thread resurrection Batman!

After reading this and a few other threads and I think I'll not bother smoothing the airbox. However, I do still have a cold air feed (prob 80mm) that I got a few years back from Badger. Do people still think adding that is a worthwhile mod? I guess since I have it then the cost issue is redundant. My brother-in-law would probably enjoy helping me fit it too.

TIA

 

[J@mes]

ditch the OEM snorkel feed and get that 80mm feed in there!

 

[oldskool]

so binning the snorkel and putting that 80mm tubing would be an improvement. puttin it behind the headlamp like in your set up?Just ordered a green filter from Bill so will this tubing help things along. where did you get the tubing from by the way?

 

[J@mes]

ebay!

 

[Jimmy-james]

80mm MAF with a narrower snorkel makes no sense to me. I'm all over this after reading this with a minimum of 80mm feed!

 

[ReDBull]

Has anyone got a close up picture of the battery relocation brackets and measurements so I can have a go at making some. I guess there no longer available to buy?

 

[D.K]

I've not got the sizes anymore but heres some old pictures.

 

[ReDBull]

Thanks for the photos that's a big help.