My GN had a hypertech chip in it when I bought it and before I found this site I bought a Poston chip for the stock 28# injectors to replace it. A few months after that I found a guy who had Direct Scan, It showed that the car was detonating bad.
Do you have a scanmaster? If not, I'd suggest one of those first to see how the car is responding to the chip, and don't push the car too hard before you have a way to monitor knock. I'd also suggest checking into an Extender chip or a TurboTweak chip, they both have the latest technology and other nice features, like anti-theft and timing/fuel adjustments.
