for a while a few audi owners and myself have been running a k04 but not to its full potential. The problem i was having was the car would make full boost however after around 4300-5000 rpms my boost would just plumet and drop and the car was put into limp mode. This began to irritate me because you can feel the car begin to pull then all of a sudden i would loose all power. For a while dvs1.8 and myself thought it could be a run down faulty bpv or an intercooler. These seemed to be the best problems we can think of. Heat soaking is a main issue for me summer time in california so thats why an intercooler was on the list and i was running a plastic diaphram tt bpv so that could have been the problem. I then started diagnosing the problem by buying the cheapest of the two first. With the help of dvs i baught the turbo xs h-34 diverter valve. The difference between the h-25 and the h-34 is that the h-25 is a direct fit to the a4 on the intake and exhaust side but the h-34 is not. People who i wont mention their names(you know who you are) told me i should return my h-34 and get the h-25 because its the same valve but the h-25 is a direct fit.. WELLL i hate to break it to you but its not. After talking to turboxs and the person i baught it from, i was told that the h-25 is a much smaller and crapier valve than the h-34, the h-34 houses a much bigger piston and holds boost much beter than the h-25 and its smaller piston. So anyway its time to install this valve. Dvs and i made a custom hose running from the diverter vavle to the intake using a larger diameter radiator hose off of an old school mazda 323. (you can pick up hose by the foot at your local auto shop i used this hose because it was perfectly lying in the garage). after a few hours of trouble shooting and customizing the job was complete. it went off without a hitch except for one hose blowing off on the first run but after reinstalling the hose and tightening it my problem was fixed. Valve is in, valve fit perfect, valve fixed my problem. My boost is stronger than ever, and the car pulls hard to redline. I am still going to be adding an intercooler to my project car yet the answer to my boost problem the whole time was a faulty daiphram tt bypass valve. i will post pictures of the turbo xs valve next to the tt bpv, so you can see a size difference. i also have pics of the unit installed on the car but they are lower res camera phone pics. If you have any questions or comments about the valve or the install feel free to pm me or post your thoughts or messege dvs18t to see if he can help you out as well.
Reply With Quote
My name is John.
Bookmarks