Just last night I notice that if I roll on 5th going up a slight incline at full boost (1.1 bar or so) the boost will fluctuate or oscillate by about .1 all the way to red line. While it is doing this the car will surge too. Not a great deal but just enough. I don’t notice it in any other gear but forth on hard up hill pulls. All the other times, the car moves through the gears so quick that I don’t notice it. Plus it does not happen at .8 of a bar. I could be wrong but my butt dyno states that I am a touch low on HP.

To me it sounds like I may have a slight and hard to locate boost leak. Any suggestions on how to track down a small and only apparent boost leak at high boost? But I could be wrong and my stage two twins could be going out? This does not happen if I down shift and redline the car that way. I think the car just moves too quick through the gears that way to see the surge/fluctuation/oscillation of the boost.

I will be changing the brakes pads and looking into this issue tonight and suggestions would be helpful. I have also tried searching with not much help. Maybe my keywords could be better or the fact that I only read the title could be why I missed it. So…if any one is a master searcher that can help that would be appreciated.

I guess I am leaning and hoping for a slight boost leak that only appears under full load and full boost.

P.S. I am non seq with a hks evc controlling boost. Never had issues yet. The rest is in my sig.

Thanks a Bunch
Joe

edit: well I couldn't redline 5th, ran out of road. Darn. But 4th yes and the problem occured but much less. I also moved through the RPM range of that gear quicker then 5th so that may have something to do with it. Thanks Again.

 

Could also be an exhaust leak. I need to look at that to.