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billjam billjam is offline
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Join Date: Aug 2007
Location: Perth, Western Australia
Posts: 1,985
Lma-3 & lc-1

Here's how I did it - with pics

I rearranged some of the parts in the left rear of the engine bay to fit in the LC-1, RPM solenoid and test switch/LED for LC-1.

LC-1 is cable tied to a small aluminum bracket that is screwed to underside of lip of rear fender inner panel. This location is just perfect for the length of lead from the O2 sensor if sensor is in the area of the turbo.

Cables from LC-1, RPM wire and 4mm rubber hose for boost are bundled and run down front LH corner of engine bay, past fuel pump and through an existing blank rubber plug into the rear footwell.

The LC-1 cables were not long enough to go to my preferred location under the RH seat so I had to cut and splice in some extra wire. I did this for all wires including the serial cables. I bought a couple of metres of the serial cable wire and extended both of them, but if I were doing it again, I would take the extra length I needed from the Serial IN cable by shortening it and leaving it terminated (with the terminator plug) close to the LC-1.
I used two layers of small shrink wrap on each soldered cable join and larger shrink wrap over each bundle - love that stuff!

The aux-box is mounted on a bracket that places it just under the front of the RH seat. In this position, I can easily access it for calibration, to see its display and to plug in my laptop (or LM-1).
Near to the aux-box are two terminal boxes that I used for bringing all the wires together (from dash, engine bay and aux-box). While I was in there, I also included three spare wires in the loom from the engine bay in case I want to add extra sensors in future.
A common earth post (5mm bolt) is fitted to the seat support next to the aux-box for all the various earth wires.

The vacuum/boost hose tee's off at the aux-box and runs up under the dash to my boost gauge along with the wires to the Innovate G5 AFR gauge and power wires feeding the aux-box. My vacuum/boost hose is connected at the throttle body.

I spliced into the speedo sensor wire where it comes into the tunnel and that wire is connected to aux-box for speed logging. I am having a problem with getting logical readings from this connection if anyone can assist?
I was going to clip all these cables and the hose to the floor or rear of the footwell, but they actually sit unobtrusively under the carpet in the back corner of the floor so I haven't worried about securing them at all.

And if that's not enough info, here's the wiring diagram ...

1988 Carrera - 3.6 engine (with ITBs, COPs, MS3X) and a whole set of turbo body panels waiting in the attic.
Day job ...
Memories: '68 912, '72 911T, '80 911SC, '84 911, '85 930, '86 930, '87 911
Old 01-06-2010, 06:26 PM
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