New to the forum, new to audi and all related with them. I am however not new to cars. I have done a lot of research but have still come up scratching my head.

I sold my Miata and bought an 03 a4 1.8t Quattro, a bit neglected really, but overall the car is solid. Bought a new crank sensor(code), and a timing belt kit with gates racing belt, new plugs. Will be doing oil change, and changing all fluids when the parts come in.

-First, I am new to tuning maf cars, and attempting to do so on higher levels. Started out on Hondas, all you needed was hondata and power was easy. Then I started working on mazdas, Miata specifically, they do have maf's, but megasquirt ecu, iat, and a map sensor later you have the potential of easy power.

Now I have searched high and low, and I haven't found any viable standalone ecm's for the audi, 034 might be the only one I found, but over 2k for an ecu is a bit much. Haltech would be cheaper, but would run into issues with the cluster and what have you.

So I am trying to understand how chips work, lets just say apr to keep it simple. Do they use a tune for your elevation with a custom map. Or does the chip simply up the boost and change the map, ecu makes other corrections as far as air via the maf?

-2nd...As much as I love this car, it feels great down low, but it just falls flat on it's face after 4500 or so. Really not a fan of this ko3, and from what I have read, the k04 isn't much better. I have read about the gtrs, gt28rs(common in miatas) and the biiger turbo options. In the near future, a bigger turbo would deffinetly be in the works.

My plan/thought would be to do supporting mods on the k03 as of now, chip, catless downpipe, exhaust, fmic, and other bits. Come tax return, buy a bolt on gt28rs in junction with the other parts already installed, injectors and a new chip. But then the delimma I don't yet understand, seeing as how the n75 valve and ecu are going to control the boost, from my understanding using a mbc will cause the ecu to go into limp mode.

-3. Another question, everywhere I read, recommended to buy vag com. I have read threads people saying to get the cheap ebay variant, and seen others swearing only on ross tech stuff. $250 seems a bit steep compared to $10. And that said, is there a difference between buying the $10 ebay one, and getting the license for $100 from ross tech?

-I do apologize as this may be difficult to understand. This platform isn't like anything I have ever had, and the more I read, the more questions I have. The more confused I get. If someone can help steer me in the right direction I would appreciate it.

 

as far as apr goes on b6+ its an ecu flash. they rewrite the ecu eeprom with their file. secondly the bosch me7 is a load based ecu. it uses maf/throttle angle position and wide band O2 sensor to calculate the Load and adjust fuel trim/ignition and boost accordingly.

secondly, the ecu has various fuel/ignition maps on it and based on driving conditions and outside environment, the ecu can compensate/calculate the fuel curve to use. this is because it is load based.

if you look at Maestro eurodyne ME7 tuning suite or nefmoto, you will see that you can use your stock ecu and remap it. this negates the reason to get standalone.

also both map and maf are incorperated in the system, however the map sensor is only used to monitor boost, because given throttle angle,maf variable and load will "request" more or less boost. this is done so by the ecu controlling the N75 valve/solenoid which regulates pressure seen by the wastegate.