I recently went to the dyno after adding a 2.5 pulley to my 2012 GT500 stock blower car. Only mods are a JLT 123 with the 2.5 pulley. I do have a triple pass H/E that will be going on soon. Temps that day were low 70's 26% humidity. My engine temp was around 165 at start and 195 at end of pulls. IAT2 I believe was max of 120deg. We were using fans on the engine, H/E, and underside of the car. All pulls were done in 4th gear. Any thoughts why it is flat from 5500 deyond. No detonation or knock retard. During most of the pull the knock sensor was adding timing. Base timing I saw was 16 and knock sensor was adding up to 2.25 degrees of timing.