CS Downpipe...flapper clearance issue (plus wrap)

[AutoEuphoria]

I took my downpipe off today to see if the wategate was hitting the metal flap as had been reported by other people (see picture below). Turns out, there was a fingernail sized scratch in the metal plate, indicating that I was suffering from the same phenomenon. This might be causing my boost spikes...the wastegate may not be opening all the way, causing overboosting. It had been noted before, and I guess is kind of common with the CS downpipe. I ended up filing down the metal by about 1/2...I might take a little more off tomorrow.

Anyway, I ended up wrapping the DP while I had it out using some DEI wrap I had laying around from a previous car. Turned out well, and hopefully will help keep the underhood temps down a little

So, here is a picture of the wastegate (not my picture...found elsewhere on this forum - lestat13's)

This is what happens with the CS downpipe...apparently that flapper hits the metal piece separating the divorced wastegate section and the rest of the downpipe (again, not my picture - these were ChrisK's...look at the white mark)

In my case, there was actually a gouge in the metal, shaped and sized about the same as a fingernail and a couple thousandths deep by my estimation, from where the wastegate flapper was coming into contact with that piece of metal, causing it to not open all the way (possibly causing boost spike). I filed it down a bit tonight...might take a little more off tomorrow.

Hopefully that will give enough clearance.

Here's a pic of the wrapping job:

Anyway, hopefully that takes care of the boost spike issue. If not...well, I'm not sure. Hopefully it'll go away once it warms up. If it doesn't I'll probably take it off again and look to see if it's still hitting that piece of metal. I'm not even sure it's the flapper causing that gouge, but it looks to be about the same shape if anything. The curvature seems to match that of the wastegate flapper.

 

[PCspeed3]

I dont get the "advantage" of the divorced wastegate setup, is it possible to trim (cut) that little prat out where it hits. May want to take a look at the waste gate itself to get an idea of what you will need for clearance. Good luck with the re-install.

 

[wisniaPl]

anyone else having that problem??

 

[07speed3]

I'm curiouse to see if that is the problem also because I recall someone else tested it with the stock turbo and said there is not a ckearence issue but it would still (nice to know for sure befor I install mine haha

 

[AutoEuphoria]

Well, I'm still getting the overboosting, but at least I was able to get the DP wrapped. I sent off a datalog chart to Cobb...maybe they can help me. I'm currently seeing sustained peak boost of 22+ psi during a 3rd gear pull from 3000 RPM. On the current tune it should be holding at 19.