From my enquiries it is a high power mod ie 350+ and is supposed to give a stonger fix of head to block it came from the WRC enviroment i think it costs about £350 as the block has to be machined as well as the cost of the studs. PJ Motorsport could give you a price for all. I have used the ARP stud kit myself £125 which are a big improvement on standard but i only intend to run stage 1. regards ED