I'm just wondering what the best (most easily accessible) vac source is on the '15+ WRX for a boost gauge. I understand the one that comes with the car should be fine; but, I prefer to have an external one. Any advice would be great. Pictures are even better.
I believe most people T into the vacuum line going to the bypass valve. Pretty simple.. then run the new vacuum line through a grommet in the firewall. There should be one behind the clutch somewhere.
There should be a good number of vacuum connections on the top of the engine.. brake booster, FPR manifold reference, MAP sensor, etc. I'm not familiar with what the intake manifold on the new models looks like, but the older ones had fittings all over them.