I run out at thunderhill with quite a long straightaway (120+) and trust me, my stock gt power was just fine. even with a long straight, most of the time you're spending is in corners. I really do recommend you focus on weight reduction (which will do more for you lap times wise and will be more noticeable than power....and it's free!). getting more seat time is key to going faster. I will say this to even an experienced guy...more power is the last thing you need. I recommend some racing seats for sure and putting the car on a diet and just keep getting out there. especially if you've only been out there a few times. in the grand scheme of things, more power will net you what....a couple mph at the end of the straight? that's not a lot of time saved over that long of a course. now think of it the other way, less weight, car can handle through the corners with more ease, which ultimately gives you a few things....braking later and harder into the corners, carrying more speed into the corners, getting back to the gas sooner, which ultimately means you get off the corner faster, and then bam...at the end of the straight you just got onto...you have the same amount of speed or close to it that you would have had by adding that hp. and all....for free! and....that money you didn't spend on motor mods, you just spent on another track day...where you shaved even more time off your laps with that extra seat time.