APR Chip
 

Does anyone have any expierence wiht this product? I am thinking about getting one. Does it help wiht the Lag on the Turbo? And is it true that it slips by the dealers cause I still have my warranty that I do not want to jeapordize...Thanks

I have a soldered in version of the APR chip
 

And I can tell you that it does not slip by the dealer. I've read posts in the past that flashing the ECU is less likely to be detected. That said, changing the ECU (regardless of the mechanism) can always be detected...

Chips void engine warranties.

I'm stock until 02/2007 when my CPO runs out...
 

I wonder what's the best tuner shop around Stamford, CT. I should start deciding on what brand of chip to install...

You can get 2 programs (stock+ 91 or 93) and security lock out
 

which does a good job of keeping your dealer from discovering that you have a chip. Some dealers are far more scrutinizing than others in this respect though.
Lag is more a function of turbo design put people do say that it feels like less lag after the chip which is likely just feeling thr increased power.
Upgraded diverters and throttle body boot/bi-pipe are strongly recommended when ECU is upgraded.
<img src="http://www.goapr.com/Audi/images/dyno_a6_stage_i.gif">

Regarding chips and warranties...
 

Having a chip doesn't automatically void the warranty from what I understand. The chip has to be the prooven cause of the damage. My local dealer is pretty cool about it if you don't try to be sneaky.
The newer APR chips are flash coded so they look like stock, and the VAG's aren't supposed to detect them.

Turbo lag is caused by the lack of sufficient exhaust gasses to spin the turbos at low RMP so it probably won't help that much. It will allow more boost so once the turbos kick in...hang on!

There are tens of thousands of happy APR, Revo, GIAC, MTM, O.CT customers out there
 

though not so many in here. (Sorry if I left someone's favorite out.)

You may have more luck searching the B5 S4 forum archives for opinions where there is more enthusiasm (and experience) with modification of the 2.7 engine. There is no undetectable programing to my knowledge, so you'll have to decide if you want to risk portions of your car's warranty for the performance benefit, which is substantial.

Now fix your sig and don't hesitate to use that little search button up top;-)

Flash programing only means that a dealer can legitimately and routinely
 

reflash your ECU to factory parameters. As this method becomes more universal among aftermarket software tuners, you'll see more dealers simply reflashing (overwriting) your code if they suspect something. It's a cat and mouse game that those with something to loose (AoA) will figure out a way to win.

Personally, when I was at that stage, I simply bought an additional ECU and swapped the stock one back in when I went for warranty service. Pretty foolproof.

You can go into a bank with a gun and ask them to give you money too!

If by foolproof you mean fraudulent, then you are correct.