I'm going to install my Zeitronix this weekend and need to pull the wires for MAP and EGT through the firewall. Also need to pull a vacuum line into the cabin for another sensor.

Where is the best spot to go through? Is there an unused grommet for this, or should I go through the steering boot, etc?

 

A topic that has been covered far too many times...

But being the nice guy I am here are a few choices;

You can use the grommet for your steering column.

Or

You can use the grommet underneath your glove box that your main wiring harness passes through.

I believe there is another behind the passenger front strut tower but hear its fairly difficult to route through.

 

You are correct. I have my vac line to my boost gauge through that along with the harness for my oil pressure. I can get a picture if you'd like...

 

I appreciate the feedback. I searched (really!) and found a couple threads with the same two options you offered (steering boot, ECU) then the boost gauge article in the "how-to" section where the guy drilled a new hole...

I was fishing for consensus on if one was better than another, leaks in the winter, gets in the way during clutch swaps, burns up due to the downpipe, or if there simply is a dedicated spot like on the BRZ / Mustang / etc. Sounds like there's no magic spot.

Cheers