From The Vault: A Qatari C6 RS6 Build

07 Jan From The Vault: A Qatari C6 RS6 Build

This week, your humble blogger/narrator will unearth a story from long ago (2010), when OJ was in the Middle East for a few months. He came across a gentleman and an RS6, and the rest is legendary. Enjoy!

A request was made. Sheik Al-Thani (not the ruler Al-Thani) had just purchased a 2010 RS6; as a matter of fact, I was there when he purchased it. Within 2 hours of becoming the proud new owner of Audi’s Super Sedan, he had decided that 580 bhp was not enough. His request was simple — he wanted more power, and he wanted me to make that happen. The time frame he wanted it done within, however, wasn’t as straightforward.

Now, before I lay out our task at hand, I will give a brief and very rudimentary lesson on making power with factory turbos. For the most part, it follows a well-defined, but at times complex formula, so for the sake of time I will simplify it to the bare basics.

1. Increase airflow or density

This usually equates to increasing boost, but can also be done by removing restrictions in either the exhaust or the intake side.

2. Keep it safe and under control

The more air you take in, the more fuel you should be using. I personally like to keep turbo cars in the high 11 AFR area, as I feel it is generally the safest range to operate in.
Once your AFR is set I then start with timing. Being wrong here can quickly cause problems, but if you can keep temps down and detonation from occurring, you can make lots of power here.

Keeping things under control refers to consistent power, and generally speaking, reliable power comes from reliable heat management. Increase boost out of the compressors’ efficiency range and the turbo will function like a heat gun. If intake air temps skyrocket, the ECU will start to pull timing, causing a power loss, or worse, detonation.

So now, back to that timeline…

11 days. From the time of inception to completion we have 11 days.

Ok, time to move quickly, and if you were following along before, this is where the formula comes in. To make any sort of power on the already ludicrous RS6 we will need to first increase boost. To accommodate this need we will provide a custom ECU flash tune. Not only will flash tuning allow us to increase boost, but we can also improve throttle response, tune the timing tables and remove some of the protective torque limiting.

Now that we are moving more air in, it only makes sense to help move more air out. We need to decrease exhaust restriction, as I see the exhaust as a crucial step to making real noticeable power on this car. Ideally, removing primary and secondary catalytic converters will be the best way to make power, as this car will be primarily used on the racetrack and is therefore emissions exempt.

We need to keep everything cool and under control. The Audi’s intercooler efficiency shouldn’t be exceeded with what we plan to do; however, we are in a region of the world where temperatures can climb into the 130 F range. Because of this, we will be using chemical intercooling, otherwise known as water/meth injection.

Now that we have the plan, this is where things get complicated. Time constraints are only marginally allowing us enough time to get the water/meth set up. None of the aftermarket companies I contacted can get an exhaust to us in the Middle East with enough leftover time to install in 11 days. This is a problem. The best and quickest option for us would be to hack off the primary and secondary cats on the stock exhaust (again, this will be a race car, so it’s emissions exempt). However, with my welding standards, I could never let some quick, hack-and-fill MIG job done by some poorly trained and poorly paid laborer be associated with my company’s final product. This is an RS6, it is an automotive masterpiece. To do anything to blemish this level of prestige and presence this car has would be a mortal sin. There is only one answer to this problem — Craig Hegland.

However, there was a small problem with the answer to this problem; Craig was nowhere near Doha. As a matter of fact, Craig was holding down the fort at Fluid’s base of operations, way back in Illinois. Time was beginning to wind down, so things needed to be dealt with quickly. I sent pictures of the current RS6 exhaust setup, as well as some rough dimensions to Craig, who basically planned this entire midsection on the fly, while trying to pack a rough collection of the items needed for this undertaking. Originally, the owner of this RS6 wanted to fabricate and install both the exhaust midsection and an FIA-compliant roll cage within the 11 day time frame. Knowing the amount of work that goes into a certified roll cage is far beyond 11 days worth of work, I managed to talk him down to just the midsection. This gave us some extra time, but not much, especially since our materials were few and far between.

Craig’s mission was essential; he had to secure a welder and enough materials to bring out to Doha, and then manage to fly over here with all of it. Thankfully, welders and materials like tungsten are easy to come across in the United States in a short span of time and with a somewhat limited budget. After managing to find most of the items, Craig hopped on the airplane (leaving the US for his first time, to boot!) and the next day, Craig arrived and was ready to work quite early in the morning.

Thankfully, Hani was able to find us a shop to work in, but it wasn’t the most ideal of shops in which to cut, weld and sand. The garage was essentially a single room containing two lifts very close to one another, without much space between the lifts and the walls. You seriously couldn’t have two cars on the lifts with both their doors open at once – it just wouldn’t fit. Our table was two Land Rover tires and a piece of particleboard. Craig’s welding chair was a piece of plastic patio furniture. It was well over 110 degrees outside. Conditions were ripe for pretty much nothing, nonetheless some serious metalwork. In order to save some time, Craig arrived with the RS6’s x-pipe pre-welded, ready to be cut and matched to the rest of the piping, all of which managed to arrive in Doha in a suitcase without a single word from customs.

Craig’s items were limited, and there were still many things he needed, like gas for the welder, sandpaper, grinders, sanders, etc. It was my job to go out and find those things as I had been living here for over 3 months at this point. In Doha, there’s a section of town specifically dedicated to pretty much everything. Most of the things I needed were found within the Industrial Section of Doha, which felt like a mixture between a Tunisian street market and downtown Flint, Michigan. Abandoned cars on bricks lined the edges of the street as vendors took up residence in the spaces in between. And here I was, driving through this dilapidated part of town in a dropped BMW 750li with 20” Alpina wheels, with a tank of argon hanging out the rear window. To make matters even better, the car’s air conditioning wasn’t working. It was quite a sight to be seen, I can assure you.

Upon returning to the shop with the necessary materials, Craig and I went to work on the exhaust. Hani stood at the ready, translating our English for the gentlemen kind enough to lend us their shop for the next couple days. Hani also played the role of provider, keeping us content with plenty of cheeseburgers and Red Bull. We didn’t get much sleep during the construction of the midsection, but the Red Bull wouldn’t have let us get much sleep either way. The lack of sleep added frustration not only to Craig and myself, but also to the owners of the garage, whose normal cycles of break taking and relaxation were jilted by these Americans who wouldn’t stop working if the world stopped turning.

Over the next few days, the conditions were a little on the “roughing it” side of things, but we accomplished everything we needed to accomplish. Craig had finished the RS6’s midsection, deleting the primary catalytic converters and adding the x-pipe, and he had also installed a water/meth injection system and a sprint booster (for eliminating that pesky drive-by-wire throttle lag). The owner seemed pleased right off the bat, so we went out for a test drive of the RS6 to ensure that everything was working properly. After flirting with speeds more than triple the limit on standard US highways, and setting my personal vehicle speed record, we decided everything was ready to be handed back over to the owner.

It was a ridiculous premise to fly Craig out with welding materials in tow to construct a midsection with almost no prep work and almost nothing that would normally exist in a fabrication shop, but it paid off in the end. Funny enough, the owner came back to us after having the car for a little while, and complained that we’d made it too fast (roughly translated back to us). I believe that’s the first time somebody has ever returned to us, dissatisfied with the fact that we made their car faster. But, no matter, everything eventually worked out for the best. We had worked our asses off (especially Craig) for the better part of five days, so we knew that there was only one thing that needed to happen before we returned home.

We went out to a hotel bar and got absolutely hammered.