smoothing the airbox

90jb11

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hi whats this smoothing the airbox all about what does it do and is there a tutorial about it?
thanks
 
If you have a look though my progress thread (link in my sig) you'll see my pics and the logs I did. You basically remove all the ridges from inside the box and sand it as smooth as you can. This means that there won't be as much resistance in the box for the air to pass over. I got an extra 3bhp and 7lbft from doing it on my S3.
 
i just have a 1.8 no turbo will it be as effective?
 
cheers mate think i will give it a go is it a quick and easy job or can it be a *****?
 
cheers mate think i will give it a go is it a quick and easy job or can it be a *****?

It takes a while to do.

The easiest way I found was to use an extremely sharp stanley knife to score the bottom of each plastic fin then use a pair of pliers to snap the fin off. This will leave you will some tiny little lips to sand down. If you have a dremmel and a sanding pad it's a lot quicker to do.
 
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It's not a particularly quick job but it's easy for sure/ What he said
 
thanks alot mate will do that at weekend and i have a debur air tool at work that will take the pips of so that should be easy
 
thanks alot mate will do that at weekend and i have a debur air tool at work that will take the pips of so that should be easy

Go easy on the sanding in the middle of the bottom part of the box as it's quite thin by the moulded circle bit (you'll see what I mean) and it's quite easy to go through the box.
 
I'm also looking to do this on my S3 in prep for the Vortex cone from the GB.
How easy is it to take the airbox out? Is it just a few screws to undo?
 
Yep, I definetly meant Jetex! lol. Dunno where vortex came from :s

I may find a donor airbox to practice with before hand then.
 
If you have a look in Tuffty's build thread you'll see how he cut the box to fit the cone in. It's a fair bit of hassle but if you want it to look OE under the bonnet then it's a good thing to do.
 

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