Installed Voodoo Boost Controller ... now can't boost under 14

[hsk8te2006]

Hi Everyone,

I'm having a straneg problem.

I just installed a voodoo IV boost controller tonight, and I can't seem to bost less that 14psi.

My car is mostly stock, with a 1g crushed BOV, a few gauges properly sourced, and a K&N filter.

I hooked the nipple opposite the screw to the turbo outlet (where the stock boost control line was hooked up), and the side nipple to the wastegate. I used piping as short as possible.

No matter how loose I set it, even 1/2 turn short of havign the screw fall out, I can't seem to boost less than a constant 14psi.

Suggestions?

 

[Matt4g63]

that is odd, you might want to get a new one.... i sat here trying to think of the problem and all i can think of is possibly built wrong?

 

[hsk8te2006]

I have a thought...

The way I mounted the MBC, the screw and bracket wasn't 100% tight, and could spin around the screw a little bit. So, I zip-tied the pressure line (from the turbo to the MBC) to a small hose in the engine bay to stabilize the MBC, and now I'm wondering if maybe I constricted the line enough so that it creats a bottleneck, resulting in a higher boost pressure on teh turbo side than on the MBC side of teh zip-tie. I think that might explain the reason I'm boosting around 14 even though it's set to around 7.

I'll try releasing the zip-tie tomorrow night or Monday to see if it helps the problem.

Anyone else's thoughts?

 

[95CarbonEclipse]

I know this might sound stupid, but are you sure you're still on the stock T25? I'm 99% sure that you are, but I have to ask.

 

[hsk8te2006]

Previous owner kept the car 100% stock, and I haven't changed teh turbo, therefore a T-25 it should be.

 

[Artago]

I have a thought...

The way I mounted the MBC, the screw and bracket wasn't 100% tight, and could spin around the screw a little bit. So, I zip-tied the pressure line (from the turbo to the MBC) to a small hose in the engine bay to stabilize the MBC, and now I'm wondering if maybe I constricted the line enough so that it creats a bottleneck, resulting in a higher boost pressure on teh turbo side than on the MBC side of teh zip-tie. I think that might explain the reason I'm boosting around 14 even though it's set to around 7.

I'll try releasing the zip-tie tomorrow night or Monday to see if it helps the problem.

Anyone else's thoughts?

Can you draw us a diagram of the MBC and how it's hooked up to everything.

Are you running it through the BCS?

It's almost impossible to pinch a hose 100% and at 99% pinched it should still work normally. My guess is you have it hooked up wrong or tapped improperly.

Tom

 

[Artago]

I know this might sound stupid, but are you sure you're still on the stock T25? I'm 99% sure that you are, but I have to ask.

I was thinking the same thing. I guess he just wants to lower boost to save on gas. Ironically the best way to save on gas is to buy a big late spooling turbo. D Assuming you don't have a lead foot)

 

[hsk8te2006]

Hi,

The BCS is no longer coupled to the system. It is still plugged in, but I have capped its nipples, as well as the corresponding nipple on the flex pipe.

I'm just trying to be able to control my boost level, and having 14 as a minimum doesn't seem right, or safe.

Here's a diagram of how I hooked it up:

Thanks for your help figuring this one out!

Jonathan

 

[p1s70np0w3r]

Looks like you have it right you try switching it, also where you get it from?

 

[always_broken]

Should I hook the 14b up to the 2g BCS or have a hose running from the compressor to the jpipe nipple?

If the 2g BCS is the better option, does it matter which line goes to what on the solenoid?

 

[hsk8te2006]

Looks like you have it right you try switching it, also where you get it from?

I got it directly from the manufacturer's website.

Well, here's an update:

I removed the zip tie today, and tried adjusting the screw some more.

First, to see if the screw and spring/ball system was working, i tried to dial the boost up to see if it even worked. Well, it did... I actually hit 23psi for a second or two, and it was still climbing, so it definitely works to turn the boost up.

After that, I tried to dial ti back down, and I foun dthat if I loosened the screw, until it was about 1/2 turn from totally falling out, I was able to get it to limit the boost to only 13 psi.

Now, I know I should be able to limit to the stock spring rate of 7psi, but honestly I can't imagine why I would ever want it below 13psi anyway. Thoughts?

 

[hsk8te2006]

Should I hook the 14b up to the 2g BCS or have a hose running from the compressor to the jpipe nipple?

If the 2g BCS is the better option, does it matter which line goes to what on the solenoid?

IF you hook the 14b up to the 2g bcs, you'll end up running stock levels of boost (12 psi in a 2g). I would highly recommend you get some form fo boost controller instead, so you can raise the boost levels if you install the appropriate supporting mods.

Also, if you do choose to use the 2g bcs, then your pressure source needs to hook up to the lower nipple, with the top nipple being hooked up to a hose that vents back into your intake tract (after the MAS), ideally the stock nipple towards the upper (MAS) end of the flex pipe.

 

[kenamond]

hsk8te2006: When you pull it apart, is the spring still somewhat compressed (do you have to compress the spring a bit to get the threads to grab when you put it back together)? If so, the ball is being held against the orifice at its loosest setting, and it's apparently enough to raise boost about 4psi (T25 WGA opens at 9psi I believe). If you want lower boost, you might be able to overcompress the spring so that it ends up being a bit shorter, but I also don't want you damaging your MBC because I'm a moron and just don' t know it.

 

[DontStartModdin]

I had this same problem on my 1g with a Slowboy boost controller. I couldn't set the boost below 14psi.

I sent it back to them, and they sent me a new one. This one works great.

I'm not sure what caused the first one to fail though. I'd try sending it back if I was you. If you get a new one and it does the same thing, then you know it's something else.

Just my .02.

 

[hsk8te2006]

Ok... so, considering that I broke the nipple off of my intake return pipe from the BCS, I cannot hook up the stock BCS any longer. How would I control boost while the MBCs are in transit?.... Hooking a line directly from the turbo nipple to the wastgate nipple for the time being?

 

[always_broken]

Ok... so, considering that I broke the nipple off of my intake return pipe from the BCS, I cannot hook up the stock BCS any longer. How would I control boost while the MBCs are in transit?.... Hooking a line directly from the turbo nipple to the wastgate nipple for the time being?

I know it'll work on 14b's, not sure about the t25 if that's what you have.

 

[kenamond]

Ok... so, considering that I broke the nipple off of my intake return pipe from the BCS, I cannot hook up the stock BCS any longer. How would I control boost while the MBCs are in transit?.... Hooking a line directly from the turbo nipple to the wastgate nipple for the time being?

That should work. Make sure the vaccuum line doesn't leak, and you should hold about 9psi boost. Be careful on your first test drive to make sure boost is being properly/safely limited.