General Wiring, LT-1 Harness, Guages and Electrical Systems

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General Wiring, LT-1 Harness, Guages and Electrical Systems Part 1

Mark checked out many wiring companies. All have good features. Mark chose to use Haywire Inc. vehicle wiring unit. Mark is also using the H.I.T.injection harness for LT-1's and 700R-4 Lock-up kit from Haywire, but we will get into that later on.

The Deluxe unit features 21 fuses, 4 relays and 2 flasher plugs. All of the wires are terminated into a factory style plug. In other words, once you have the wires run to everything, you simply plug it into the fuse panel. Mark and I both really liked that idea.

Mark states that in addition to the fuse panel, you'll notice the completeness of the Haywire Deluxe kit is impressive. It's a good idea to lay out the harness and separate it into the different sub-harnesses, such as headlight section, taillight section, etc. This way you can get familiar with it and pre-plan where wiring will be needed to run and drill the necessary holes for grommets.

A sheetmetal bracket was welded to the underside of the cowl to mount the fuse panel and harness.

Mark also took the time to weld tabs to the instrument opening. They will be to mount the 1/4" aluminum dash insert Mark's making. It's good to look a few steps down the road, so you don't "build yourself into a corner."

Here is a more finished view of the instrument panel. Vintage style gauges, by Classic Instruments will nicely do the job. The gauges feature a programmable speedometer, tachometer and a quad gauge. Always place your gauges where they are easy for you to read!

As I stated before, we will really get into the nitty-gritty of the wiring as Mark gets farther along.

LT-1 Wiring

Here is the Haywire Inc. LT-1 engine harness from Haywire. It comes with all the necessary connectors to plug directly into the G.M. sensors and computer. Mark plans on mounting the comuter under the passenger's side seat.

Mark wanted to increase the clearance around the steam line fitting on the back of the passenger's side head and needed a feed through for the engine harness, so these two needs were combined. An oval was machined from some 3/8" steel and tack welded to the inside of the firewall after enlarging the opening. It will be welded flush on the engine side when the body is removed for the last time. A split cover was then fabricated from aluminum sheet to hold the grommet.

Since the 700R4 transmission cannot be controlled by the '94 LT-1 computer, one of Haywire Inc. 700R4 Lockup kits was utilized. The pressure switch is screwed into one of the service ports in the passenger's side of the transmission. The harness then plugs directly into the transmission. The vacuum switch can then be mounted to best suite your application.

General Wiring, LT-1 Harness, Guages and Electrical Systems Part 2