Grounds....

Tuners use a heavy ground buss cable that has multiple screw terminals. Snakes around the entire engine bay, usually neon (yuck) but does tie in all grounds to common.
[ame="http://www.ebay.com/itm/UNIVERSAL-Racing-Kit-D1-Super-Earth-5-Point-GROUNDING-System-Wire-STRAP-Cables-Y-/221553457007?hash=item33959d776f&vxp=mtr"]Universal Racing Kit D1 Super Earth 5 Point Grounding System Wire Strap Cables Y | eBay[/ame]