Hey guys - I haven't had time to get to the dyno, but looking at some of the other trucks - I have seen them putting down anywhere from 1000 - 1150 on the dyno. Most of the dyno graphs I have seen have been on 250's with the Spartan tunes. I haven't seen any from a 450 yet. As soon as I get time I will be visiting the dyno to get some numbers. I have seen a couple of posts on the Spartan boards of 350's and 450's running in the mid to high 13's on diesel only (no nitrous). Spartan has a 250 putting down 567 RWHP on fuel only running 12.52@109 and 617 RWHP on nitrous. The 250 tune is running close to 500 RWHP and 1025 RWTQ - I am running the 275 tune. I love diesels!!!!!