date unknown

There is barely enough room to do a 2.0 setup in the standard 1.8 block that comes in the B5 A4.

Even the stock 1.8t didnt have a great rod ratio just ok. I went with a VW ABA which had the best rod ratio for any compatable block.
Rod ratio is an indicator of the piston speed at TDC and BDC, with TDC being more important. The longer a piston stays at the top the better gas exchange you get and this is extremely important on a turbo engine. It gives the engine time to scavenge or push the exhaust out b4 you start the intake stroke, no exhaust in the combustion mix is very worthwhile. Also slowing the pistons help reduce shock load and will make for a longer lasting engine. I also like a long strroke from past experience to maintain top end power. Thats my 2 cents, but I would advise you to look up rod ratio and the reason you wish to keep pistons slow. BTW on any kit be careful where the rods come from, at 1 time the Eagle rods were failing, I also think they were made in China.
Good luck,
you are getting ready to spend from 5-25,000 to do either end of a stroker engine so make sure you need the extra inches. I know that 400crank can be made on the non-stroke cars.
Rod