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Discussion Starter · #1 ·
Hey guys,

I'm looking for a vacuum line to tee off of for my boost gauge and I'm having a REALLY hard time finding a line. There is one right off of the intake manifold, near the throttle body, but its 1/2 inch in diameter and I'm having absolutely no luck finding a tee that goes from 1/2 inch to the size needed for the boost gauge solenoid (AEM Digital Boost Gauge), which is 1/4 inch. The tee needed for that would have to be 1/2 to 1/2 to 1/4. Not something readily available.

Would anyone happen to have a vacuum diagram or know of where another line is that I can tee off of?

Also, as far as wiring goes (I am also installing a wideband), would anyone happen to have a diagram or know what colors wires are what? I am splicing into the wires located within the panel, on the drivers side of the dash. I could probably splice off of the parking brake or head light switch; I just have NO idea what wires are what. I basically just need a 12v (switched) and ground.

Thanks for any help!

Shane
 

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i did it the "easy" way lol and used the tee that came with the turbosmart bov, as it was intended by ts as an easy way to hook up a boost gauge (or anything else requiring vacuum). i also ordered an ebay boost gauge install kit in order to get the multitude of fittings necessary to make it all work :LOL:

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for the power, i just used a switched 12v in the pass side fuse box instead of hooking into the headlight wiring or fuse as i was lazy lol but kind of like it always lit up anyway.

hope that helps some.
 

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For the tee you are looking for check Home Depot or Lowes in the plumbing section, check the lawn irrigation section also. You might find a tee for 1/2 to 1/2 to 1/4. The drip irrigation uses 1/4 lines.
 

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Where are you locating the gauge?
Also, why wideband? The stocker is a wideband and can be logged by the factory software, or by a comprehensive OBD2 like an AUTEL.
 

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Discussion Starter · #5 ·
Where are you locating the gauge?
Also, why wideband? The stocker is a wideband and can be logged by the factory software, or by a comprehensive OBD2 like an AUTEL.
Im building a custom pod for the two gauges. I’m hoping to make a separate post for that later as I’m really excited about it and feel like it may catch on as a great alternative to where people are mounting gauges currently.

As far as why a wideband: I just finished modifying my car quite a bit and with the new mods and tune, I want to be able to monitor the AFR’s, in real time, with accuracy at all times. It’s peace of mind for me.
 

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It's your choice.
I am also considering a boost gauge, there is a Defi that matches really well, it's designed for a Subaru Legacy.
The spot that I'm eying is to the left of the Command "tablet", between it and the cluster.

To me, the biggest finding with the boost gauge, is to see if somehow Mercedes managed to give the Launch Control Antilag features.

Subaru was able to do so with their Spec C, with the Group N Rom, without using a dedicated fuel injector, just by manipulating valve advance and spark advance, with properly timing the fuel injection event.

But the other that I would choose is a oil pressure gauge.

As far as AFR, to me certain data is best logged, because the trends are more representative than the momentary values. I would read a log and see what the load was, boost and AFR, and that paints a picture for me.
 

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Discussion Starter · #7 ·
It's your choice.
I am also considering a boost gauge, there is a Defi that matches really well, it's designed for a Subaru Legacy.
The spot that I'm eying is to the left of the Command "tablet", between it and the cluster.

To me, the biggest finding with the boost gauge, is to see if somehow Mercedes managed to give the Launch Control Antilag features.

Subaru was able to do so with their Spec C, with the Group N Rom, without using a dedicated fuel injector, just by manipulating valve advance and spark advance, with properly timing the fuel injection event.

But the other that I would choose is a oil pressure gauge.

As far as AFR, to me certain data is best logged, because the trends are more representative than the momentary values. I would read a log and see what the load was, boost and AFR, and that paints a picture for me.
It's your choice.
I am also considering a boost gauge, there is a Defi that matches really well, it's designed for a Subaru Legacy.
The spot that I'm eying is to the left of the Command "tablet", between it and the cluster.

To me, the biggest finding with the boost gauge, is to see if somehow Mercedes managed to give the Launch Control Antilag features.

Subaru was able to do so with their Spec C, with the Group N Rom, without using a dedicated fuel injector, just by manipulating valve advance and spark advance, with properly timing the fuel injection event.

But the other that I would choose is a oil pressure gauge.

As far as AFR, to me certain data is best logged, because the trends are more representative than the momentary values. I would read a log and see what the load was, boost and AFR, and that paints a picture for me.
I'm curious to know about the anti lag as well. I also contemplated an oil pressure gauge. That might be something for a little later though.

I do log all of my AFRs for my tuner... but logged info is information "after the fact". I like having the wideband in front of me so I can see AFRs and know if something isn't right.

For example: I started my car for the first time since all of my upgrades yesterday. I'm also running E85. Anyway, AFRs looked good at cold start, but slowly turned to SUPER lien conditions (off the chart lien) after idling for a minute or two. Had I not of known that, I probably would have tried to drive the car and that could have led to some other serious problems. All that was logged though, sent over and my tune is getting a revision. Slow process haha... Regardless, for me, wideband is a safety net and helps with diagnostics a bit. Same with boost gauge. Kind of keep an eye on things.
 
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