if you owna 1.8t and you have a chip and a few other goodies, you need this next. i have GIAC, ecs n75, strat DV, and remus muffler with stock dp and exhaust and this pipe frees up so much power its incredible. for the $160 it costs its a no brainer. the turbo is louder, the car pulls MUCH harder, and it just sounds/feels better all around.

thats it, im just happy with it. i have a small leak somewhere that i havent had a chance to fix yet, but i dont think im loosing any back pressure and i dont think its effecting performance. im just **** and dont like the little flutter sound up to 4000rpms.

 

3" seems like a lot for a ko3. i only had a 2.5" on my t3t4

 

it is, but i think 3" test pipe with a 2.5" DP/cat back is supposed to flow the best. this test pipe will work with k03, k04, and BT set ups, so when i go k04 i wont have to upgrade. obviously you will get more out of with a larger turbo though

 

actually a 2.5" would be the best and match the flow for the ko4.. with a 3" tp to 2.5" downpipe you will cause uneeded turbulance in the system with the step down in diameter size..

 

I have a 3" tp, stock dp, and 2.75" dp back milltek exhaust. I have no problems other than a small leak between the tp/turbo on the manifold side bolt- due to ATP's shitty design. I have no complaints about the setup other than ATP's design. Performance improved a lot after the test pipe.

 

The outlet of a K03 is 3" so if you have a 2.5" TP you will actually have a 1/4" step down at the turbo so that will create even more turbulance than a 3" TP to 2.5" DP. I am running the ATP TP and am happy with it. I have seen a 3" inlet tapered to a 2.5 outlet TP for sell.