RarlyL8
>>>So all ITBs should be tied together for a common vacuum signal. How does TWM do this?<<<
All 3 runners are tied together internally within the casting. Then a simple port nipple taps in.
Here's a pic which shows exactly how all 3 ports are tied together:
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SHOWN WITH THE VACUUM PORT HIGHLIGHTED
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FROM ANOTHER ANGLE
>>>What do the high dollar tuners do about the brakes on a 930?<<<
The same as everyone else! DW SD said it....
You tap the same vacuum source. But you have a check valve installed so you don't pressurize the vacuum booster.
Also, if you don't have enough vacuum to power the brakes, or if you want to have a "reserve" of vacuum, you have a "vacuum resovior" T into the line, behind the check valve. This sort of thing is standard issue on turbo cars since they can only build vacuum when the car is off boost (actually.... you can use a venturi to get vacuum on boost, which 944 turbos do... but you don't need it and it's often removed).
In the case of my 911SC with the 3.6L and the TWM ITB's, I have found that there is enough vacuum w/o the resovior (tapping into the vacuum source shown in the pictures).
TonyG