Originally Posted by Quicksilvers

From the pics it looks like you have resonators I do not see any catalytic converters there. How did you past inspection or smog? The code P0430 should be a faulty camshaft position sensor. I had this same code on my 350Z and I had to replace the camshaft position sensor with a Denso brand sensor. Did the last owner install aftermarket camshafts? I have hear of faulty O2 sensors on these cars with or without a code being thrown. The only fuel you should be using in your 370Z is 91 octane gasoline or higher. Be careful using octane booster because curtain brands can damage catalytic converters and 02 sensors. Read the instructions before using any octane booster and make sure it says it is safe for catalytic converters and O2 sensors. A lot of brands of octane booster are for racing or off road use only.