Scott Posted July 1, 2008 Share Posted July 1, 2008 (edited) Got, what i considered, a half decent MBC valve off of ebay (Rspec or something like that). Anyway, i fitted it and turned it right down so that the actuator wouldn't see the boost. I expected my boost gauge to go off the scale but it did nothing. I then tried turning it all the way out in case it was a mistake in the instructions but the same thing happened. To make sure everything was ok at my end i took the line off the actuator alltogether and the thing boosted to 1.5 bar (very quickly too), of course i came right off the pedal but that prooved that the actuator, wastegate etc is all fine. Is there a range in these valves (ball & spring type)? Just wondering if all the way up means open and all the way down means open too lol. Thanks Oh, just to be clear when i say it "did nothing" i mean it boosted to 0.8-0.9bar as usual. Edited July 1, 2008 by Scott (see edit history) Link to comment Share on other sites More sharing options...
Scott Posted July 1, 2008 Author Share Posted July 1, 2008 Anyone? Would opening up this hole in the top help? Link to comment Share on other sites More sharing options...
Chris Wilson Posted July 1, 2008 Share Posted July 1, 2008 You need a restrictor pill in the wastegate line, the systems pipe size overwhelms the orifice size in your valve, even when wide open, so the wastegate still gets enough pressure to open. Link to comment Share on other sites More sharing options...
Scott Posted July 1, 2008 Author Share Posted July 1, 2008 Restrictor pill? Can i just open up the hole of the valve? Thanks Link to comment Share on other sites More sharing options...
Chris Wilson Posted July 1, 2008 Share Posted July 1, 2008 No, it needs a pill, IMO. Link to comment Share on other sites More sharing options...
Scott Posted July 1, 2008 Author Share Posted July 1, 2008 Just had a read around and i think i might be plumbing it in wrong. I have put the MBC between the Wastegate VSV and the Wastegate Actuator. In one of the threads it says i should have it between the turbo and the wastegate actuator. Would this make a difference? One thing i did notice was when the 2nd turbo was coming online, i was seeing around a 0.4bar drop in boost before it went back up. This only happened with the MBC plumbed in between the VSV and the wastegate. When i take out the MBC and have it plumbed in as normal it only drops very slightly as per the norm. I read that the VSV-wastegate actuator plumbing is to try and combat this so its making me think i would be better between the turbo and the actuator. Thanks Link to comment Share on other sites More sharing options...
jaymdee Posted July 1, 2008 Share Posted July 1, 2008 Just had a read around and i think i might be plumbing it in wrong. I have put the MBC between the Wastegate VSV and the Wastegate Actuator. In one of the threads it says i should have it between the turbo and the wastegate actuator. Would this make a difference? Thanks Yes. it needs to be in the pipe from Turbo to Actuator. Check to see if the MBC barb has a tiny hole to let air leak from, as this must be uncovered or it spikes all over the place (well, mine did). You also need to cut the hose which between the two VSVs and cap both ends IIRC. i found placing a bleed valve between turbo and actuator was much easier and gave better results Link to comment Share on other sites More sharing options...
Recommended Posts
Please sign in to comment
You will be able to leave a comment after signing in
Sign In Now