when my pump went out, i had trouble getting it over 70 mph, it literally wouldnt do it. when i thought it was going out i raced my friends hyundai elantra and we were right next to eachother. thats how slow the srt is without its s/c. i dont think your pump is out. you either overestimated its speed or there is another issue with the car. its one of those two though.