I'm wondering the same thing, I have a 97 auto, and put in the TST 230 HP kit when I first got it, in late 96. I had it dyno tested last month, and with the plate slid forward slightly, I was getting 278. 9 HP to the roller, and the torque went to 646. I have 135k on it now, & am wondering if that might be a lot of miles on the original injectors. At wide open throttle, I'm squeezing a lof of fuel through the old ones that are in there now. Would I notice any difference in power or fuel mileage with the 215 injectors? What's the next step up from 215's?