I think alot of people here probably misunderstand you, however, I know exactly what youre going through. Albeit my car makes quite a bit of power, so the situation was about 100x worse. What you're experiencing is a throttle cut. Only the 07's have this function, why I really dont know, but especially in highly modified cars, its a royal pain in the ass if you accidently hit the rev limit, specifically if youre spinning in 1st/2nd or for some of us 3rd, and 4th lol.
You can actually VERY easily install and 08+ ecu. Its as simple as removing the stock ecu, plugging it in, than learning the immobilizer to the new ECU using a paperclip or wire to short two pins on the OBDII connector. The only important thing is that you get an auto ECU if you have an auto, and vice-versa if you have a manual. I have a writeup on learning the immobilizer over on SL - heres a link -
Scroll down to post #11, my username is thendawg on SL.