westwest888

In general, I'm not a fan of radically altering the factory intake system. To stay legal in California you're supposed to keep the stock airbox. I have no issue with that as the car seems to be able to find plenty of air to suck in, particularly when the blower creates vacuum forces.

I did make two important changes. First, the OE intake pipe connecting the airbox to the throttle body is garbage. It's a weird shape with sound deadening resonators in it and it's easy to crush with your hand. Some vendors sell silicon tubes of various strengths as a replacement. The crappy ones crush under the vacuum pressure of the blower. Recent revisions don't do that. The only pipe I've ever trusted is APR's "stage 2" air intake pipe, which is made of hard carbon fiber and doesn't flex. On either end there is a flexible cuff and a silicon cuff, with metal clamps. It's been solid for 2+ years now, never requiring adjustment.

APR B8 S4/S5 Carbonio Stage II Back Pipe Intake System CI100024 $224.99

https://store.goapr.com/products/APR...ke-System.html

Second, I swapped out the OE paper filter for an AWE cotton filter. It fits in the stock airbox with no problem. I view the airbox as a good thing. It keeps dust and heat away from the intake. The rest of my engine has a fine layer of dry dirt around it from some of the places I drive in rural CA. I replace the filter about every 18 months.

AWE Tuning S-FLO Filter 2710-11010 1 $89.00
AWE Tuning Audi SQ5/Q5 3.0T S-FLO Filter | AWE Tuning

Bobby Kinstle

I seriously doubt the smog check guys look that carefully. I live in a big city and the random places I go to only check the things required to make the machine work.

Engine? Yep
Gas cap? Yep
CEL? Nope
Tailpipe hoopajoo: Passed

That'll be 75 bucks.

westwest888

It's pretty strict. No airbox mods. No cat deletes. Those are immediate fails. There are placards under the hood that have the emissions control information for your year that tell them what components to look for.

iNfiNkC

make sure you remove the snow screen from the inlet also, that thing block a ton of air flow. Yea california sucks, i just swap my stock box on when it comes time for smog.

Bobby Kinstle

Remember you can get your car smogged at any station in the entire state. If you live anywhere near a big city, go find some crap garage gas station where the guy barely speaks english. He won't care.

westwest888

Clearly I'm getting good results with this (high horsepower), and I don't have to hide from anyone. Being below legal is not fun after a certain age. You just don't want the hassle.

primetime

West, You would get better results from an open intake it's not debatable really... I've done and others have done testing via data logs and strip passes and the open intake performs better in every case... As for the legallity issue... lol!

Bobby Kinstle

If you go from 034 motorsports south on osgood drive past automall where it turns into warm springs, and south to Mission, there is a 76 station on the corner of mission and warm springs. That's where I get my car smogged and I guarantee you he won't give a second look at your mods.

westwest888

I'm having trouble believing there is an immediate gain beyond what's statistically significant (perhaps > 7 HP). It's merely a dust and heat shroud. I would even disqualify dyno results because the airbox has a ram air effect from the ducting to the front grill. 1/4 mile results seem valid, but I don't do 1/4 mile. I turn the car into a heat monster over 30 minutes on a dusty road course.

It's like saying if you removed the plastic housing from your vacuum cleaner it would suck more crap out of your house. When the blower is pulling at 15 PSI I don't think it would matter if I put a plastic bag around the intake. It's going to get the air from somewhere. Without the shroud, it pulls it from the hot engine bay. With the the shroud, it pulls cooler air from the ram air duct in front of the radiator.

primetime

West, I'm aware you don't like the 1/4 mile and that's fine but it's about as good of a measure of performance improvement as anything and I'll also take my logs or others that have no vested interest over any dyno numbers... As for pulling the hot air, in traffic you're correct but most of us care more about performance while driving and the intake is not pulling in hot air from the engine bay when moving and the box has a limited capacity...

What I do find odd is that you think 7hp is statistically insignificant yet you are buying a battery that weighs 45ish lbs less than stock for the weight savings... 7 hp will be more noticeable than -45lbs from the trunk of the car... It's about a 2% HP bump on stage II car vs about 1% weight decrease...