Big brake kits are are designed with proper F/R brake balance. I wouldn't mix and match calipers. Save your money and do it right the first time.
The base brakes will be fine as long as you get some decent pads and fluids in there and don't do any threshold braking. Get more seat time and take it easy on the brakes until you can upgrade.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |