I must first of all mention that I am in Australia and we do not have the choice of Kits like in USA.<br>He we have the Chioce of the MTM and Wetterauer Kit.<br>The MTM agent here charges a ridiculous amount for the MTM as compared what it is sold for in the USA and Germany. And they are in another city 500 miles away.<br>This left the Wett Kit.<br>I had to be the pioneer here. Some of you read previously I have been having some problems with the kit, well they are almost all resolved.<br>Frank Wetterauer has responded and given a lot of help in developing new Software to sort out my Problems.<br>The Essential problem is I was getting a lot of pinging which in turn causes the Motronic ECU to <br>"retard" The Final result was no extra power than what I was getting with the original Turbo and Wett 1 Bar chip.<br>The first step was to install Colder Spark Plugs Bosch Part number F2CS.<br>This reduced some pinging and got the occosional Burst of extra power.<br>Frank has developed a series of Chips for me to sort out the problem.<br>The Final Conclusion I have come to is that Austrlian Premium (Hi Octane) Unleaded which is supposed to be rated at 96RON is definately not. Even addition of 104+ ocatne boost did not make much of a difference. Currently I am running a version of chip that suites about 91 RON fuel. This gives me more power than Stock turbo with almost no pinging. With 104+ added I get no pinging.<br>The other Factor that has added to my problem is that AUDI in their infinate wisdom use the same motor with 9.5:1 compression ratio in both Non-Turbo and Turbo models. If you do your sums on this compression ratio/ PSI at 5000 rpm, you require Fuel between 100 to 108 RON!<br>Most other Turbo motors run about 8 to 8.5:1, allowing reasonable turbo pressure without pinging on common fuels.<br>I beleive this is why Audi only push 7 psi and upto about 11psi on the new models to suit<br>various fuels around the world.<br>There are tuning options to improve this situation, Richer Fuel Mix, less adavnce timing etc.<br>At the end of the Day I am happy i did buy the Wett kit as they have been helpful in sorting out<br>my unique situation. I must mention a word of caution to people buying products, and that is buy products from distributers that can modify or develop their products to suit your car if you have a problem. Be wary of idle promises especially one like "It will just bolt on and away you go". How many times have I heard this. Any modification or upgrade should be checked and tested. I was very disturbed to hear on the forum that some one was selling "Pirated Chips"<br>at a cheap price, I wonder what would happen if one of these was tuned for different fuel and you end Up with a engine failure, what happens then? I have personally seen 5 different ECU in 1.8T A4's, and the chips where Not inter-changable. Wett was able to supply a chip for each of them.<p>1.8TQM, Wett K-04, K&N, AZK Exhaust, AZK Springs&Shocks.

14.7 psi

Audi did use some wisdom here.<p>The 1.8 is a low pressure turbo. It relies on high base compression for off-boost drivability. It gets great milage, lots of lowend torque (with the small turbo). The turbo is for passing, to take advantage of cold temperatures and to make up for altitude losses. It is really a superbly designed system.<p>The new version of this motor in the tt and is a high pressure turbo. It has more lag, worse milage, and more power at the top end (larger turbo). This is an entirely different design philosophy.<p>High pressure turbos are a lot of fun, once you are past the lag. They also have serious drivability issues. I've used both and prefer the optimized- low pressure design.

<br>ko-4 turbo has the same size turbo as the k0-3; it just has greater blade angle/less clearance with the housing so it has the same airflow at low rpms/is able to maintain boost /airflow until 6000 rpms; ther should be no greater lag. Have you driven a tt with the bigger turbo? don p has the ko4 kit: don, is the lag greater with the bigger turbo?

I wish we had a tt here to drive. Nope, it's just the nature of dropping the compression ratio 8.1-5 instead of 9.5 (for detonation resistance) and putting more plumbing in the line.<p>One interesting thing: I've never seen a KKK04 taken apart. I asked some people who have installed them and was told that it was the same size expeller (the exhaust side) with a larger impeller (the cold side). So, it's really a hybrid turbo. I have seen the varying blade design on other brands of turbo (garrett, IHI). If the 04 is really the first or the second design it will have more boost, but run out at the same point as the stock. *assuming the exhaust is the limiting factor* If it is indeed a larger turbo (on the inside diameter; they are the same outside diameters), then it will lag but have a better top end. Lag would be from the inertia of the larger wheel and the lower pressure on the exhaust expeller.<p>