Overkill Ground Wiring
One of the interesting performance modifications that many sport compact owners are making has to do with the way the motor is electrically grounded. Many ground points are rather far removed from the actual chassis ground point. A good example is the coil packs that drive the spark plugs. They are grounded to the valve cover. The valve cover is bolted to the head. The head is bolted to the engine block. The engine block is bolted to the transmission. The transmission is grounded to the chassis.
People have noticed significant performance gains (5hp and 5-10 ft/lbs torque) in some applications by improving these ground points. We'll see what this does with the GTI.
I chose to use 4 gauge wire with gold plated crimp connectors. You can see an example of the wires below as well as some photos of the grounding that I did. The coil packs are now additionally grounded to the intake manifold ground point which is directly grounded to the chassis.
Ground wire before installation
Ground wire next to my keyfob for size comparison
Whole motor almost done
A little closer look
Coil pack and valve cover ground points
I later switched the routing to this so I could use my engine cover.
Passanger side ground point
Intake manifold close-up
Drivers' side Ground points
I finally got the tranny ground done. It is hard to reach, but isn't too hard to add in. Look at your Bentley Manual for guidance on finding it. It is on the drivers' side of the motor on the side of the tranny facing the battery. I took a photo of it below. It is easiest to get to it if you take the battery out.
Tranny Ground bolt
To find that bolt, look down at the shifter mechanism on top of the tranny (center of the photo above) then look immediately to the left. You'll see granny ground bolt there. Be a little careful with this. It is easy to strip it if you're hamfisted.
If you've got any questions, please drop me an e-mail. Maybe I can help with your project.
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