We have detected you're not on the correct site for the car you have selected! Click the green button below to go to the correct site.
Select your car:
Created: July 24, 2003
There is no specific large-bore (1275cc-based) head casting number that will fit the 998 engine any easier than any other. They all have the same problems - generally requiring exhaust valve relief cut-outs machined into the block and re-alignment of the front water gallery transfer ports. However, I would avoid using heads with valves bigger than 35.7mm on the intake since these are too big for most 998 engines unless they are absolutely full-race spec where top end power at high rpm is all that is required.
Created: July 11, 2001
First a brief word on head gaskets. If it is not a genuine Rover or Payen gasket, don’t use it.