More boost Issues..

Well, i drove the Q4 at Winton this weekend past, with a totally different electronic boost controller. I did not use the Pierburg valve system at all the whole day. The boost controller I was using is a self-learning system, where basically you drive the car for 14 brief episodes of full boost (ie lap one of a race..) and the system learns how to manage the wastegate. So it could hardly be more different. The funny thing is that the boost response and control of the system was damn near identical to the Pierburg system, except that I had set it to produce 1.45 bar - which it did - for a second or so - then it was back to the 1.25 bar boost (to 7100 RPM) that the original system produced.

I believe that the turbo can produce more boost, so I now need to look for other problems. Firstly I am going to try to use a wastegate actuator with a higher opening pressure (harder spring) and also i am concerned about the 'restrictors' that are in the line between the WG and the control valve.


1. has anybody else used a higher opening pressure actuator?

2. what is the purpose of the restrictors?

3. I have blown the exhaust manifold gasket (just a small breech - but I will have to pull apart a lot of stuff to fix it...) Is there an alternative to the standard exhaust manifold gasket that will last longer at 1.4 bar?


thanks.. jim~