15 replies to this topic

[ianrm]

I am/was seriously thinking of doing the airbox mod as I saw how easy it was to do at Courtneys last weekend. Then after doing a search on here remembered about the AMM problems some people had after doing it . I have thought about modding the airbox and leaving the standard filter in as I seem to recall someone saying that it was the oil on the wet filter that damaged the AMM. What is the latest consnesus ? Any experiences would be gratefully recieved. Ian.

[clipping_point]

Seem like a wise idea to leave the paper element.

[Timbo]

Ian, i did mine about a year ago and after going through 2 amm's with a foam filter, put the std one back on about 6 months ago and all has been fine ever since. I also did Bletch's about 6 months ago and he hasnt had any probs with it either.

[ianrm]

Thanks chaps . Will probably do the box mods but keep the standard filter.

[MartinS]

Whats the gain from the box mods? Martin s

[ianrm]

Better airflow . A couple of Bhp ?

[trescoman]

I have the courtenay air box mod (you know more holes and new trumpet), it had the foam filter in originally when I had the miltec fitted, but the noise was too obtrusive, and other people AMM's were blowing......so I've gone back to the paper OEM filter, still sucks , but I feel happier this way.

[clipping_point]

Whats the gain from the box mods?

Martin s

Very doubtful if this has any effect, other than the sound increasing a bit

[njc11]

Airbox mod done to my N/A... ive not had a good look at a VXT to see how the air boxes duffer....

First pic showing new hole with trumpet (bought from Maplins @ 58p 52mm diameter) The trumpet is cut down so more or less flush with the inside of the box. It also shows how far the O.E. pipe comes into the box...



This picture just shows how much pipe ive cut off....



Finally this is showing the trumpet fitted from the outside, plebty of flat area to drill the hole..




Since ive done the mod, it has nice subtle induction noise now... and feels a little better to drive... I used Courtenays replacement panel filter.... thaks to Jon at Courtenays for telling me how to do

Im just waiting on the outcome of my paint issue on the rear clam before i get my exhaust sorted... its taking ages...

Cheers

Nick

[clipping_point]

I found a cotton panel filter in mine when i replaced it. What struck me was that the filtering area is only about 50 % of the original paper one, due to less thickness, see piccy. Threw it away!

Attached Files

•  filter.jpg   17.5KB   0 downloads

[Crabash]

clipping_point, I totally agree with you on this, I came to the exact same conclusion. I tried a K&N in my 2.2 astra, IMO having a haircut would of given a bigger gain. Filter's are not undersized ristrictive pancakes like the old day's now and the paper filter, filter's out smaller particles than any of the foam or cotton filter's anyway. For me it's a OEM paper filter all the way.

[Thorney]

I've stayed OEM and happy with it. If it can cope with mine I reckon it'll cope with most.

[Crabash]

Very good point Thorney, but it's surprising how hard it is to get people to listen.

[Thorney]

Life is all about variety Some people like the extra noise but IMO it just masks the noise of the Milltek and deafens your passenger so not for me

[njc11]

Is the VXT airbox the same as the N/A?? If so, the people who have vxts with the airbox mod do you still use the standard paper filter??? The noise in my N/A is just right,its not deafening, sounds just perfect... would it go quieter if I put the paper filter back in?? I would have thought it would sound the same?? Cheers Nick

[garyk220]

VXT and NA airboxes are different shapes and have different attachment points, but the internal layout is pretty much the same. I've modified mine by removing the 2 internal restrictor cones, but not drilled an extra inlet hole, and kept the standard paper filter. The noise effect on a turbo is less obvious. What will all the whooshing and hissing from the turbo/dump valve and the noise from the Milttek. It does make the induction moise a little more obvious though