how do i install this 3 port mac valve for boost control?

[kevboost7]

Interesting. Those turbocharged engine diagrams usually has all the boost go straight into the intake valve lol. So i thought they were the same thing. 

[GTSBoy]

35 minutes ago, kevboost7 said:

Those turbocharged engine diagrams usually has all the boost go straight into the intake valve lol

Example?

[kevboost7]

On 10/24/2023 at 11:40 PM, GTSBoy said:

Example?

im talking about a generic diagram. Like this one:

[GTSBoy]

That's a diesel.

[kevboost7]

Alright, i connected everything properly, but my car isn't boosting past 7-8psi. Any ideas?

3 Port Solenoid is working, i hear it clicking. 

[TurboTapin]

2 hours ago, kevboost7 said:

Alright, i connected everything properly, but my car isn't boosting past 7-8psi. Any ideas?

3 Port Solenoid is working, i hear it clicking. 

Stock ECU or did you end up popping in that Haltech Platinum? I'm presuming the latter, if so have you set up your output, boost maps, etc.?

[kevboost7]

25 minutes ago, TurboTapin said:

Stock ECU or did you end up popping in that Haltech Platinum? I'm presuming the latter, if so have you set up your output, boost maps, etc.?

yessir, haltech platinum is in. I did multiple runs and my manifold pressure (boost pressure) never exceeds 8psi. All the settings are correct. 

Open boost with 33 hz. No matter what duty cycle % i put, it dosent change boost pressure. 

[GTSBoy]

Then....it's still not plumbed up correctly.

[kevboost7]

im about to just drive this car off a cliff

I swear i hooked up everything exactly like the diagram. could it be a boost leak?

[robbo_rb180]

1 hour ago, kevboost7 said:

im about to just drive this car off a cliff

I swear i hooked up everything exactly like the diagram. could it be a boost leak?

No as you are making wastegate pressure. If was leaking it would creep.........


Above plumbing is the way to go. Don't run lines back to plenums, exactly like the above. Short runs of hose, super easy 
Check what MAC valve you have as some can be different with how they work. Greddy are backwards to normal in my experience.

Connect reference line to wastegates directly to see what it makes, do a run and log it. Then plumb in the solenoid its internal gate so can only go one way. Run it and log it. Add 20% to whole duty cycle table do a run and log it if get a change add 5% more do a run and log it. Do this until achieve target pressure.

Will need maybe 20-30% Duty cycle to see any change in pressure from actuator preset.
If this doesn't work take it to someone who knows what they are doing, its a super simple setup that has been tried and tested for well over 20 years.

[kevboost7]

23 hours ago, robbo_rb180 said:

No as you are making wastegate pressure. If was leaking it would creep.........


Above plumbing is the way to go. Don't run lines back to plenums, exactly like the above. Short runs of hose, super easy 
Check what MAC valve you have as some can be different with how they work. Greddy are backwards to normal in my experience.

Connect reference line to wastegates directly to see what it makes, do a run and log it. Then plumb in the solenoid its internal gate so can only go one way. Run it and log it. Add 20% to whole duty cycle table do a run and log it if get a change add 5% more do a run and log it. Do this until achieve target pressure.

Will need maybe 20-30% Duty cycle to see any change in pressure from actuator preset.
If this doesn't work take it to someone who knows what they are doing, its a super simple setup that has been tried and tested for well over 20 years.

1. I thought this turbo pressure line comes from the plenum? Is there a way to get the turbo pressure line near the turbos?

2. How do i plumb in the selonoid in its internal gate so it goes only 1 way?

[Duncan]

Can you post some pics of what you have done

[joshuaho96]

On 11/15/2023 at 2:46 AM, kevboost7 said:

im about to just drive this car off a cliff

I swear i hooked up everything exactly like the diagram. could it be a boost leak?

This is just a part of learning how to modify a car.
 

10 hours ago, kevboost7 said:

1. I thought this turbo pressure line comes from the plenum? Is there a way to get the turbo pressure line near the turbos?

2. How do i plumb in the selonoid in its internal gate so it goes only 1 way?

1. When it comes from the plenum (before the throttle bodies) it accounts for the losses through the intake piping. Personally I do not think this is your problem.

2. I think the suggestion is to basically completely re-do the vacuum lines instead of using the factory setup. So basically you would plumb the turbo pressure line just after the twin turbo merge pipe. Then you would disconnect the factory hoses going into the wastegate and put in your own hose with a tee piece to join it all together.

I kind of find it hard to believe that the factory plumbing won't work for what sounds like a mostly normal configuration.

As others have said you should post clear, well-lit pictures showing what you've done. It may also be that your issue is wiring, a bad solenoid, your MAC valve actually has different port numbering/orientation than the normal ones online, etc.

[GTSBoy]

12 hours ago, kevboost7 said:

1. I thought this turbo pressure line comes from the plenum? Is there a way to get the turbo pressure line near the turbos?

1 hour ago, joshuaho96 said:

So basically you would plumb the turbo pressure line just after the twin turbo merge pipe.

This would require you to drill and tap into the alloy of the merge pipe, to put in a nipple, or weld a nipple onto the hot pipe after that point.

The reason here is that the drawing you showed, with a line coming from each compressor housing, teed together to feed the solenoid valve, only works when you have tapping points on the compressor housing, which you won't have.

12 hours ago, kevboost7 said:

How do i plumb in the selonoid in its internal gate so it goes only 1 way?

I really struggle to understand what you mean by "only goes 1 way". What was it you're trying to do there?

[joshuaho96]

20 hours ago, GTSBoy said:

This would require you to drill and tap into the alloy of the merge pipe, to put in a nipple, or weld a nipple onto the hot pipe after that point.

The reason here is that the drawing you showed, with a line coming from each compressor housing, teed together to feed the solenoid valve, only works when you have tapping points on the compressor housing, which you won't have.

I really struggle to understand what you mean by "only goes 1 way". What was it you're trying to do there?

I was thinking of putting a nipple into the factory rubber hose or the aftermarket metal pipe after the merge pipe but yes regardless it's kind of annoying and impractical. I also really don't think it should be a problem if the factory boost solenoid was working prior to this.

[GTSBoy]

Oh, yeah, there's no reason to avoid using the existing plumbing. What is there can be used to make it work properly. You just have to plumb it up correctly.

I re-iterate to the OP. If it is not working, it is NOT PLUMBED UP CORRECTLY.

And, to follow on from Joshua's repeated suggestion that the MAC valve might have differently labelled/functioning ports compared to the usual MC valves, I posted extremely clear instructions on how to work out which port is which, earlier in this thread. So there should be no excuses there either.

[kevboost7]

Hey guys, sorry i just got back from my trip to greece. 

I was able to take a video of everything. See the link. Dont judge me for the spaghetti wiring/hose mess right now lol 

 

[r32-25t]

That’s not even close to what people have been telling you to do!! 

[joshuaho96]

2 hours ago, kevboost7 said:

Hey guys, sorry i just got back from my trip to greece. 

I was able to take a video of everything. See the link. Dont judge me for the spaghetti wiring/hose mess right now lol 

 

This is what your setup is:

Port 1 - atmospheric vent
Port 2 - wastegate port
Port 3 - Pre-throttle boost source

Compared against this diagram:


So the vacuum line setup actually seems ok to me? You might need to use an air compressor or just blow through the hoses. When it's off it should connect port 3 to port 2. When it's on it should connect port 1 to port 2 instead. Set it to 90% duty cycle on the Haltech and see if that is actually happening. Don't run the engine when doing this experiment and remember to set the values back to something normal afterwards.

Put 14 psi into port 1 vacuum line and verify you can hear it venting into the intake piping before the turbos. It shouldn't hold pressure substantially.

If all the function tests check out set a boost fuel cut for something very conservative like 2 psi over wastegate boost and set the solenoid duty cycle to 90%. If you still get stuck at wastegate boost then try just running with port 2 open to atmosphere with the same conservative boost cut. Before you actually set that boost cut the way I describe see if it works at 2 psi of boost for example. You don't want to find out after the fact whether the boost cut didn't work as intended. Make sure to set a large hysteresis as well in the fuel cut so you aren't bouncing off of it.

[r32-25t]

number one port is currently plumbed into the bottom of the plenum which is a boost source