A hidden benefit to purchasing that 4 wire set would be a 33% increase in gas mileage for the Z. Kind of like the cylinder cutout method for increasing gas mileage on some of the newer cars. Well worth the price.

Ah, the old V8-6-4

well honestly can't see how you all expect to add so much more hp with out putting on the adjustable aluminum < toy car handle style > wing , and besides if you can add the lower guage grounding wires i bet you could get atleast another 30-40 horses