I will first start out by saying yes, i have done my research, and no, i still have yet to find out how to fix my problem.
With that said, here is the issue.
I bought the forge unos mbc, install it per instructions found on evom... Start up the car, boost "goes through the roof". From Clay's response in the thread below found on evom, the problem lies with the using the hard spring instead of the soft (hard hold 26 psi+, soft holds only to 19 psi). So i throw in the soft spring, no different result, boost still goes through the roof.
I have tried reversing the vac lines (fyi, val lines are brand new and are not the stock lines), tried the RRE mbc (which resulted with the same issue as the forge)... at this point, i dont know if i have 2 bum mbc's or if i am completely overlooking something.
I have been unable to find any good pictures of what the spring/ball should look like when it is "properly seated"... that may help.
Any suggestions? See below for thread i found on evom. Thanks!
Hmm, if it happens with more than one MBC, then it's either an installation error or something faulty in the system. I doubt it's the MBCs, since you've used two and have even changed springs.
You've tried a lot of things, so I'd really have to mess with it in person. Check these boxes just to be sure:
- You're using 2 brand new, unrestricted, properly-sized vaccuum lines. One goes from the compressor outlet nipple to the bottom nipple (straight down from the knob), and the other goes from the WGA to the side nipple (90* from the knob)
- You have the knob turned ALL THE WAY counterclockwise, which is minimum
- There are no pills in the lines or anywhere in the boost system
- The WGA arm is not bent
- The WG flapper is seated when the WG arm is loaded
- The springs are seated fully, which means it completely engulfs the internal nipple/knob
I am finally hitting 20 psi and tapering from there (every once in a while it will hit 23 and taper) with my forge. It turns out im an idiot and was not A. Using the soft spring B. Setting the spring all the way compressed and slowly turning the boost toward the negative side... My defi red racer gauge reads high from what i have heard, so im actually right around 19 or 21... i am hoping... I am thinking about dropping it a bit more to be on the safe side just in case my gauge is actually reading correctly.
Regular gauges read 2-3psi higher than actual due to atmospheric pressure being much lower. Your IX can run a good bit of boost with a proper tune, so I don't think you need to turn it down - just be sure to get a solid tune from someone like Tobz.
I finally have my forge mbc spiking to 21 psi, exactly where i want to, but i have noticed after tagging the 21 there is a large loss of power as it sharply tapers to 10 psi where it sits (this is at WOT mind you).
I tried reversing the vac lines (without messing with the + - knob) and it shoots to boost neverland where the boost never stops and tapers).
Thinking it was due to the soft spring not able to hold the boost pressure, i switch to the hard spring, at which it also hits 21-22 and tapers to 10 psi...
At this point, i am at a loss... when i reverse the lines, it has all the power in the world, and does not seem to be controlled at all... when i have the lines like i believe is correct it hits 21 as i like and tapers like a Sally
Not possible to get the intake snorkel syndrom without the stock intake even if you still have the snorkel attached, because even if the snorkel gets sucked up against the hood, it has no effect on air going into the filter.
For it to hit 21psi peak and then fall that much, it would have to be a huge boost leak. Have you done a pressure test? I have a nice pressure tester if you need to borrow it. I also have a compressor, so we could do the whole test, but I'm not home until late Friday.
What time friday will you be home? What is your availability for the weekend? It is possible it could be leaking big time from the charge pipes due to my recent licp install... I am checking this out tonight.
Late Friday, so that's probably out, but I'll be home all day Sat/Sun as far as I know. You could potentially come over and use my stuff, but you'd need to do the work, since I'm basically down to one arm/hand after surgery to my wrist. I can provide the tools and supervision in case you're not sure what to do. I have a water bottle with soapy water to find leaks, too.
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