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This helps with anyone that don't know what they are. On mine I built my own as well as the last 3 SUV's my wife has had. Most of them picked up in performance but the gas on trips was a noticeable improvement. Her xterra picked up 2 or 3 mpg.
On the VR4 I have the battery in the trunk and a large 2 gauge going forward to a block of phenolic resin, on that all the power wires hook in to a bus. Then from the battery I have a large gauge and a small one that is daisy chained forward hooking to the floor pan as it goes. after getting to the passenger side inter fender well It then goes everywhere, one to the trans, one to the intake, valve cover, firewall, radiator support, preatty much the more the merrier. While your at it you can also change or add another cable from the alternator to the fuse box and run another or larger to the starter. Car needs electricity to run properly and unibody cars don't have alot of welds but alot of seem sealer so anyone with a battery in the trunk and just grounded to the floor aren't doing everything they should. The people that sell battery relocation kits are doing just that. 80 to 100 for a box and a piece of wire /ubbthreads/images/graemlins/dunno.gif. If they added a second wire for ground profit margin would drop in half so they just do the old floor technique.
