Its 425". 12ish:1 compression, Street/Pump gas friendly, 4.12 bore x 4" stroke, Thitek Heads, 2.25 Ti Intakes, 1.65 Exh, Solid Roller, T & D Rockers, Jesel Lifters, my own design Cam Belt Drive, made really good power on the dyno. I dont share dyno numbers on the interwebs. Been there, done that. Nothing good comes from it. I will say it peak torqed at 6000, peak hp was at 7600. I Went to the track one time so far. Converter was too tight for this combo compared to the previous version, so it had been sent out to be loosened up. Its back in the car, waiting on new Menscer front shocks, which will be here Tuesday. Should be going out later next week.