This installation covers 75 and later Corvettes, and we mention that because of the HEI distributor. The installation will be similar on the older cars except for the distributor. The top may be intimidating, but the bottom is where most of the work will be doneand thats the same for all 63-82 Corvettes.
Chris uses only Moroso or ACDelco wires, because they seem to hold up best on these cars. Theres a bit of a difference with these wiresthe originals had tabs that poked through the top of the cap; the new ones do not.
The first step in a successful install is to number each plug wire on both ends. The two longest wires are cylinder 1 and 2; the next longest would be 3, followed by 4, then 5 and 6, and ending with 7 and 8. Notice that one end of each wire has ribs on it. This is for the plug end of the wire.
Make sure to use all of the wire separators. They help keep the spark from crossing to other wires. Also, when installing the wires on the driver side, make sure the 5 and 7 wires are not together, because the firing order (1-8-4-3-6-5-7-2) has those two cylinders firing one after the other. Once the wires are numbered and in the separators, feed them down through the rear of the engine.
Begin underneath the car by removing the shielding. The rearmost motor-mount bolt holds part of the shielding. Youll have to remove that bolt anyway, because the wires for the front two cylinders on each side have to go under the motor mount.
When we removed the shielding, we were surprised this car ran as well as it did. The two longer wires coating was deteriorated so badly we could see the inner coating. Wouldnt wanna grab these babies with the engine running! The reason for the deterioration is typically because the valve covers have leaked and the wires became soaked with oil. Hence, youll want to take care of the oil leaks, or this will be an all-too-familiar occurrence. Check out Fluid Fencing in our March issue for tips on curing this problem.
Theres a set of separators underneath the car. Once again, when youre running the wires on the driver side, make sure that wires for cylinders 5 and 7 are separated.
Put a jack under the engine. Chris uses a board between the jack and oil pan to prevent damage. Loosen the other two motor mounts so you can slide the old wires out from under the mount.
Before installing the new wires, take a few minutes and clean the block with a cleaning solvent.
With the engine clean and free of oil, installing the plug wires can actually be enjoyable. At this point, youll notice how valuable those numbers on the spark plug boots really are.
There are a few more obstacles on the passenger side. Removing the starter and some added shielding will make this job much easier. Also, our 82 has a knock sensor. You may want to disconnect this sensor so you dont damage the connector.
Run the new wires on the passenger side just like you did on the driver side, putting the front two cylinders (2 and 4) under the motor mount.
Install the shielding and starter, tighten the motor mounts, dont forget to hook up the knock sensor again, and you should be done under the car. When installing the shields, make sure you dont pinch any of the wires.
At this point, the only thing left to do is install the wires on the distributor. Starting at the connector on the cap and going clockwise, the wires should be installed 2-1-8-4-3-6-5-7. If you marked the wires on both ends at the beginning, this should be a snap.