Maybe someone with a IS can put it on a dyno for us? Do the first 3 runs with 87 octane and get your average HP/Torque numbers. Come back at a later time, having already ran 91 or higher octane for a little while, and do 3 more runs on the dyno and get your average HP/Torque numbers. This will settle the debate for the IS once and for all. If the results show that HP and Torque were higher while doing the runs on 91 or higher octane, then we will all know that there is pre-ignition using the lower octane. What do you all think? I don't have an IS or I would do it myself. Hope to be a proud owner of an IS250 very soon. Thanks everyone and have a good new year.