The factory rev limiter is set at 6250rpm, the computer stops adding fuel at this rpm in an effort to keep the car from over revving. I'm not an expert on this subject by any means so don't flame me if I don't get it all exactly right.
There's many ways to reset the rev limiter, with the rpm extender from FRPP, a custom chip or one of the many EEC tuners (Speedbrain, Tweecr, PMS, etc.). A rev extender is a couple hundred bucks from what I've seen, which seems way expensive when I can get a Tweecr for about $350 and do a ton more stuff with it. Realistically the best buy right now seems to be a Tweecr or similar setup because, while it's a little more expensive than a custom tune and/or chip or extender from what I've seen, the potential and ability to change settings as you get new parts and combinations is much greater. With a chip you have to get it reburned every time you change something. But, it is complicated and there is alot to learn in order to get your tune right.
FWIW I was at the track last weekend and was talking to a renengade racer and some of his pit guys and they all use the PMS system, both on the renegade car and on their own 12 and 11 second rides.
You don't want to rev a hydraulic roller to 7k. If you want to rev that high you need a solid roller cam. You might want to do a search on the corral on this subject, there ought to be alot of info there.
I'm in about the same boat, all I want is to extend my rev limit to about 6500 (for now
). I'm still researching it and not sure which way I'm going to go. I've also heard that many of the tuning devices like the tweecr, speedbrain et al, are best on a power adder setup and not really necessary on a n/a car.
$1000 is way more than you need to extend the rpm's. Just do a little more research and find the best option for your goals.