Captncarb

I have upgraded my 2003 A6 2.7T to K04's, subsquencly I had to add different downpipes and make the connection from there to the stock cat back X-pipe.

The car runs great but only at part throttle, when I depress the pedal too far the sound of the engine almost sounds naturally asperated and wont hardly rev above 4,500? But if I carefully find the sweet spot it hits redline easily and accellerates considerably harder than full throttle before the mod?

I'm new to Audi's and work on cars for a hobby and jet engines for work and can handle hardware but software not as much. Your inputs appreciated.

Thanks

vghostine

Hey, Im curious to know how much did you pay for the K04 kit + installation and where did you get it done?

I have an 04' A6 2.7T S-Line (automatic not manual) and I want to chip the turbo to gain 60hp and close to 90lbs torque. But some guys told me its best to replace the current turbo K03 with K04. Im thinking chipping is 500$ + replacing stock intercoolers: 1000-1500$.

The turbo itself should be around 5000$, am I wrong?

Captncarb

I paid $900.00 for a kit on E-Bay and did the install myself, (sorry no Pics) the inlet pipes have to be changed to fit the K04's and was part of the kit, however the turbo's had to be reindexed (rotated center section and compressor independently) in order to fit properly, and I believe the reason for the low cost, after doing so I was concerned about the actuator adjustment and used a pullscale to check the wastgate poundage to open fully. I discovered the new acuators are junk (26lbs vs 32lbs for the originals) so I used the old ones and adjusted the wastegates to equal movement (I went with 3/8") which is a little tighter than the K03's were.

There are alot of different kits out there for widely varied prices, $5000.00 is the high end of the scale but should minimize the modifications needed for installation. My A6 is rated @ 250hp stock, your A4 may already be higher from the start.

For longevity purposes the K04's are much better when running boost in the teens which is where you will be pushing the K03's to if you chip it for that 60+ hp. They just won't last very long, also I noticed the entry point to the turbine on the exhaust side is about 1/2 the size of the K04's, the engine just can't breath requiring more boost to make the same hp numbers.

One last point, doing all that you mentioned I believe will get you more than just 60hp and the automatics (mine is tip?) are questionable at that much hp...

K04-S4

Congrats on the upgrades!

I would take the line off the bottom of N75 and apply light regulated air pressure to the wastegate line T while another person checks under car to ensure waste gate actuators are opening equally and staying open while holding pressure. Suggest start with ~3 psi and increase slowly until actuators open. If there is a leak in the wastegate line circuit it will do funny things like you describe. I doubt it's a software issue as K04's run just fine on both stock and stage x programming. Maybe a failing N75 valve or air leaks in other N75 lines? Maybe lookup N249 as it plays a role in boost. Sticky BPVs? Pressure Test Intake with say 10psi?

The stock Tip Trans will take Stage1 / 2 as long as it is handled respectfully. Strongly recommend a trans flush with new filter every 100K KMs for the 2.7T vehicles. The Tip will handle full Stage 3 at 20/21psi boost but be prepared to open it up sooner than expected. The stock Tip clutch packs begin to slip with very high torque and the Torque Converter should be upgraded for properly supporting Stage 3. Cole Ford in the US was running full Stage 3 on a stock Tip for years with no problems.

Captncarb

K04-S4

Thanks for your input, I did this upgrade while I changed the engine due to timing belt failure so I have some spare parts to troubleshoot with. Is the N249 the valve going to the DV's? I'm also not sure about BPV's.. or are we talking the same thing just different acronym?

I also have a new problem, I recently went to a car wash and sprayed down the engine, the next morning when starting the car instead of rotation I got a vibrating sound coming from the headlights (usually occurs seconds after turning the key to ignition)? once I threw a battery charger on, it started and continued to start on it's own until the next day when I took a trip of 200+ miles and there was some rain, after shutting it off the same thing happened but this time jump starting would not get it going and had to get it towed to where I was staying, during removal from the flat bed (nose of car pointing up) the truck driver was able to start the car 3 times? once the car was on level ground it stopped starting again, If I roll the car to a slightly nose up position and the vibration of the headlights does not occur it will start? over the next 2 days this problem occured intermitantly but seems to have stopped occuring over the last 24hr period. Is there some kind of saftey disable if the headlights are not aimed right?

K04-S4

N75 is the valve going to the T that connects the Wastegate Actuators which are mounted on the Turbo housing.

BPV = By Pass Valve aka DV and no I'm not trying to start an argument

Sounds like some diag time is needed regarding the no start issue.

Captncarb

I had installed a manual controller thats adjustable, removing the checkball and spring improved it considerably, however the fitting only had 1/8" nipples creating a restriction and thus a spike in initial boost application which I think was causing the computer to go into a protective mode and open up the wastegates and DV's? Stock boost is better than a second of spike and then nothing...

Is there a way to have in cab adjustable boost and maintain the factory controlling for normal conditions? or am I asking too much..

What valve is the N249? I'm guessing it is the one going to the DV's

The no-start problem is non existant for now, I'm hoping it was just a wet connector after washing the engine...!

Thanks for your knowledge

K04-S4

Manual Boost Controller is old school, nice on one hand but a pain on the other. Personally I would use modern N75 managed by Motronic ECU for 2.7T. The ball and spring removed on the MBC can create gremlins.


N249 controls Diverter Valves:

Audi C5 A6 Quattro 2.7T > Engine > Electrical > ES#248500 N249 Solenoid Valve - 078906283A

Captncarb

Nice diagram, sounds like changing the ECU is the way to do it (chip)... Either way it's fun to learn how this stuff works.

Do you have a diagram of the N249?

Thanks again

Tomas8878

Ok so do you still read this forum? I was looking online and i have this same problem and need to know which way is best way to get it going better!!