Chumpaumpalumpa
Proven Member
- 1,554
- 303
- Jun 16, 2014
-
La Habra,
California
So in an endeavor to learn what was going on with the car, I have some questions about the turbo system. So my turbo is internally gated and vents to atmosphere off the O2 housing. Its obvious when it opens because it gets much louder. I had a Holset HX-35 actuator on it and bench testing it with an air compressor, it would START to open at 20 PSI. It would not FULLY open until 30 PSI. I am running 22 PSI. The turbine housing was cracked pretty bad (pics here http://www.dsmtuners.com/threads/what-housing-can-i-use.497022/ ) and there were a couple small pre turbo leaks and one very small one on the IC piping where the nipple for the feed to the MBC is.. It would spool very slow from 5-10 PSI so it was easy to hear when it started to crack open. The MBC (a Hallman unit) was backed all the way out. From my understanding, this means the wastegate should open up at wastegate pressure (20 PSI in my case) and is not possible to open sooner. I made sure the MBC was hooked up properly and the wastegate was even 6 turns (1 hole) tight. It clearly sounded like it was opening at 5-7 PSI and sometimes even 10 PSI (it varied and didn't seem consistent with anything i.e. temp, elevation). On top of that the boost would spike to 25 PSI in 4th if I let it. How could the gate be opening that soon? or was it something else entirely that I was hearing? You could smell a bunch of exhaust when you heard it open as well. Does anyone have a clue what was happening?
Edit: Is wastegate spring pressure referring to fully open or starting to open?
I have since gotten a new hotside and new gaskets and have done all I can to take care of any leaks when the car goes back together. Though if an item is typically forgotten about please remind me.
Things I've since gotten:
New hotside
Head to Mani gasket
Mani to turbo gasket
O2 housing gasket
DP gasket
Fixed IC nipple leak
GTP35 actuator (Starts opening at 15 PSI)
Edit: Is wastegate spring pressure referring to fully open or starting to open?
I have since gotten a new hotside and new gaskets and have done all I can to take care of any leaks when the car goes back together. Though if an item is typically forgotten about please remind me.
Things I've since gotten:
New hotside
Head to Mani gasket
Mani to turbo gasket
O2 housing gasket
DP gasket
Fixed IC nipple leak
GTP35 actuator (Starts opening at 15 PSI)
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