I just acquired oil pressure, oil temp and cht gauges and am wondering how others have wired them. Do you pass the wires through the tunnel? It looks nearly impossible to pull them through the original rubber sheath with the main harness and I'd rather not drill holes in the firewall.

thanks,
Tom

It is not that hard to work the wires through the existing wire loom grommet. Double the wire over a thin blunt rod (I use a screw driver) and push it through into the tunnel. Once started, you can push the wire from behind a little. Then go the the cabin and open up the access hole at the back of the tunnel. You can pull the rest of the wire up that way. its not hard, but a little tedious.

Zach

+1 to Zach. That's what I did with mine.

OK great - I hadn't tried - it just looked hard so I wimped out and thought I'd ask. Thanks!

there was a hole in my fire wall into the tunnel so I made a armored wiring harness. I shoved my wires through some fuel hose and then into my firewall. I like the way it came out, however I did not run enough wires. I ran them for a CHT, oil pressure, and oil temp, but I added an external oil cooler and put an LED in my oil temp gauge to indicate when the cooler fan was on. Moral: Add more wires than you think you're going to need.

Click to view attachment

Good point. In fact I'm considering an external oil cooler but would rather avoid it. Outside temps in MT rarely exceed 90F and are almost always below 80F. Motor is a Raby 2270. I might run an extra wire just in case.

drill a hole, and sleave a bunch of wires (you may want to add stuff in future, extra temp gages, fans, etc.... use a sleeve , tape teh wires togtehr and sleeve them outside of car, tehn run teh hole sleeved bundle at once thru the tunnel, use grommetns on teh holes it passes thru.

90F ambient is not too cold to prevent too hot oil, so use care, make sure you have a calibrated oil temp gage.