The head swap really surprised me. All we changed is the head, swapped the full ported head and side mount intake done by B&B Tooling(Bruce Block) onto the truck last night. Went from 7.30 to 7.08. Thank god it made some progress. Makes me feel better about getting only 4 hours sleep last night trying to get the truck ready to race today. LOL. The funny thing is that the tuning, or lack there of, only allows us to let it shift at 2400 rpms. If we could turn it harder and shift later, this thing should really come to life. Cant wait for Bob and Marco to release some more tuning for these 6.7s.