3 Worth It Mods for your B8.5 Audi A4
Disclaimer: This article is just my opinion; I am no expert, and will probably have many that disagree. To each their own. Feel free to comment below!
Why I bought an A4
I am one of those car guys that feels naked without a car. I live in the city, and frankly do not need a car. But cars, to me, are not about need; they are about passion, the feeling you get when you drive on a curvy road, and the orgasmic satisfaction of hearing the exhaust note on hard pulls and downshifts.
After being "naked" for a full 2 years in grad school and 1 after graduating, it was time for me to "clothe" myself. I knew I wanted something good in snow, practical (i.e. could fit 4), had a manual, and most of all, was super fun to drive. I also knew that I did not want an SUV or a Subaru.
That left either a BMW or an Audi. Having owned a BMW in the past, I almost bought a 330xi until I drove an A4 Quattro. A 3 year used one with ~20K miles was right in my price range, and even with the slight turbo lag and non-existent top end power, the drive felt amazing. That feeling was further intensified with the loads of mechanical grip (thanks to the AWD system). The technophile in me was overjoyed with the 4 year old MMI system (no sarcasm intended) and all it could do. Even though I couldn't find a clean manual, I bought an automatic within weeks of my test drive (the auto box is actually 0.3 seconds faster to 60).
I waited 2 years (read: an absolute eternity) to start modding my car. I still had the certified warranty. But as soon as that last day hit, I was at the shop giggling with excitement like a 5 year old on Christmas morning. I literally could not sleep the entire night. No joke.
Mod Number 1: Delete the Middle Resonator
How many A4 B8 owners out there think the car is way to quiet? It's like someone who recently lost their voice due to a cold and wants to cheer on their favorite sports team. They try to yell in support as loudly as possible, but nothing but a few measly decibels come out. They know they have more in them, but feel frustrated that the cold is restricting their true abilities.
That is essentially what "zee Germans" did with the A4. Think of Audi as the "virus" and the middle resonator as the "cold." The car wants you to hear more, but is wrongfully restricted by its creators. Getting rid of that "cold" results in such a glorious sound, very much reminiscent of Fiat Abarths and Alfa Romeos. I personally felt as if I had added a bit of parmigiano to my sauerkraut and sausage -- it was like driving a whole new car! The gurgles and turbo exhaust notes truly gave me that orgasmic satisfaction I was so missing before. The best part: there is no drone during highway driving. It is exhaust heaven.
Mod Number 2: Air Filter Swap
Ever want to hear a tiny bit more of your turbo but not so much that it drowns out the exhaust note, or worse, makes your German car sound like a cheap modded up import? That's basically how I felt after getting rid of the resonator.
There are a few ways of achieving this result. The most promising is to swap out the stock air filter for the aFe Power Pro Dry S (see Other Mods below for more ways). For $60, yes this is 4 times the price of a regular replacement, but it does give you that extra sound and can be cleaned every year to maintain the highest performance standards. Plus, this is a super easy mod to do by yourself. There are plenty of YouTube videos that outline how to put in a new air filter. All you need is a screwdriver, the Internet, and a bit of brain power.
The factory air boxes in these cars are pretty good, so save yourself the big bucks and get one of these instead of a full air intake swap. If you're flowing in the dough, you could get a $500 cold air intake for an extra 10-20 hp but that'd be the same as paying $500 for only an extra grain in your multi-grain bread. Just not worth it.
Mod Number 3: APR Stage 1 Tune
Ok girls and boys, this is the big one. Before you take the plunge, make sure you have done the 2 mods mentioned above. This is a software tune that works best when you've made all the hardware updates you want. The resonator delete makes the car more like a car and the air filter upgrade allows the engine to breathe better. All in preparation for this, the biggie.
From the factory, the B8.5 A4 makes 220hp and 258 lb-ft, which is reasonable but nothing to boast about. This roughly translates to a power to weight ratio of ~0.061. Now assume you go get the $499-$599 + labor APR Stage 1. This is pretty much like taking a baby that only knows how to sit up and giving her the ability to full on walk the entire room (I would say run but then I'd be misleading you).
The software updates the engine control unit such that the car now makes 270 hp and 329 lb-ft, which translates to a power to weight ratio of 0.075. To put that into perspective, an S4 from the same year has a ratio of 0.085 but would cost you at least $10K more. But these figures do require you to not be cheap at fill your car with at least 91 octane fuel. Can I get an amen??
The best part of this mod though -- even more than the monstrous (relatively speaking) acceleration -- is the POP you get from the exhaust on high rev upshifts. Oh. My. God. The first time I heard it, I kid you not, I squealed out loud. In technical terms, this happens when the engine changes RPMs rapidly. This creates a high pressure difference in the exhaust airs. Once this air leaves the end of the exhaust, the difference in pressure causes a loud "pop" sound. The rapid change in RPMs is due to the APR tune, and the lack of restriction on the exhaust air is due to the resonator delete.
TL;DR -- Go and do these mods and thank me later.
*Turbo Inlet Hose -- You can switch out the factory hose that feeds air from the intake to the turbo. This will cost you ~$100 if you install it yourself (easy to do), but will only really increase the turbo sound by a little bit. Given the exhaust upgrade above, I don't think this is worth it.
*Turbo Muffler Delete -- You can delete the turbo muffler at the bottom of the engine to hear more of the turbo. However, parts for this will cost ~$135 and unless you have a way to jack the car up, installation will be another $80-$100. Based on cost analysis, it's not worth it in my book.
*Brakes -- Cross drilled rotors might go a long way for those "spirited" drives. The rotors on these cars can get warped if you drive/brake really hard so allowing the heat to dissipate more effectively might help. I actually will get these once my brakes are due for service.
*Any cosmetic mods -- I am no longer a teenager. Plus, I think these cars are quite good looking from the factory. I prefer the 18in wheels that I have over the ones you get in the higher end trims (Prestige) too.
*Springs and coils -- The car could be a tiny bit lower. I wish I had the sport suspension package that drops the ride height by ~23mm. I think it would look better, and of course on windy roads, handle better as well. I would be okay with the slight day to day discomfort too.
*APR Stage 2 -- This would require me installing a down pipe to the car. I live in California, and with this new part, my car would not pass smog. I am pretty handy, but not enough to uninstall this pipe every time I have to smog it. And paying for that every few years isn't worth it for me. Yes, the power gains are pretty impressive, but then you would probably also want upgraded brakes, air filter, and suspension to make it actually fun. At that point, I'd probably get an S4.