ztriumph

Hi Everyone,

Looking for some help. I feel I've exhausted the search options here (and in google). I have an 86' 951 that's stock except for vitesse chip, 3 bar FPR, test pipe and venturi delete. All hoses/jboot have been replaced and all maintenance done in the last 3 years including new BOV, shimmed WG, etc.

The problem i am having is that I am bleeding off boost in the upper RPM range. i know this happens to an extent with these cars, but I'm peaking around 11psi and then it drops to 6psi by the time i hit 5.5-6k rpm's. I plan on adding a 3' exhaust and either a MBC or Tial WG with an upgraded spring (looking for about 13psi) but want to solve this issue prior to introducing more variables to the equation.

Any ideas on why the boost is bleeding off to that extent? do you guys think thats normal?

Thanks in advance

bw993

11 psi is the max. boost for a stock 951 with stock waste gate. To get more boost, you will need to bypass the CV and go to a MBC with a Tial WG.

Willard Bridgham 3

The stock k26/6 turbo also limits boost by design.

ztriumph

Thanks for the replies - just to be clear not looking for more boost, actually just looking to hold the boost longer at the 11psi peak...

Paulyy

Im sorry, but this is not true. The k26/6 can only flow enough air to support ~280 rwhp. at 10psi, the turbo should hold its boost to redline. from what i can recall i had about 11-12 psi at redline but peaked at 15psi. reason being it cannot flow enough air to sustain the 15psi at redline therefore you get a pressure drop.

Is this always been happening? or something that started to happen?

fejjj