because it's become unavailable, but maybe you can find one used. I wish I had the money for an S3 hose kit. Still, I'm not sure what CA law says about modifying the intake to a degree that would be difficult to not notice during a smog check.

Installation: While the hose simply replaces the stock accordeon tube between MAF and plenum ("air intake silencer" per Audi), it takes a little effort to make the hose fit perfectly without overly bending and indenting. I removed the airbox and shaped its rubber bushings/perches a little to lower the airbox about 1/4."
Why do those most excellent ABA clamps have slotted crews? They should have Philips heads! Damn Swedes. ;-)

Observation: After I removed the MAF sensor shroud and after widening the MAF interior dimter slightly, I noticd a pronounced swoosh noise with the engine on. The S2 hose kit does the same, and I can hear a rushing air noise up to going about 40 with the windows rolled down.

Performane: I don't know yet, but I suspect I'll need more than just a stock throttle body to take advantage of the S2 hose kit.

I finally hit 8000 miles on my M1 5w40 so, hopefully, I'm going to change it this weekend and take a sample for oil analysis...if you're interested.

I also put 8k miles on it, so we can compare, especially if you use Blackstone. I suggest you get the Terry Dyson analysis, it's certainly worth it, as he knows how to interpret the numbers, while everyone else is groping around in the dark. The total is then $35, I think.

Make sure the oil is hot when you take your sample. I'm sure you knew that!

That way you can tell if the oil still had legs. The total base number can also show sticky or worn rings.

So far I passed all smog checks witj flying colors, even when my O2 sensors and MAF were shot.

They'll never notice an S2 hose kit anyway. However, I'd be worried with an S3 hose kit installed.

I was thinking about doing this, but I only have ~3k miles on my 5w-40!

Just ask them to send you a free oil sample kit. It might take a couple weeks until you get it.

You can include a check when you send the oil sample in. You may want to write a note and ask for the Terry Dyson analysis (interpretation of your UOA), which goes far and beyond what Blackstone will tell you.<ul><li><a href="http://www.blackstone-labs.com/free_test_kit.html">Blackstone Labs</a></li></ul>