What do you mean? Are you wanting to install a hardened seat FOR the 2.14" intake valve, or for the exhaust with 2.14" intakes already installed? I installed hardened exhaust seats for a 1.81" exhaust, and then cut for the 2.14" intake. The seat 45 degree angle can touch the exhaust seat insert, therefore you must do the exhaust seat install first. If you are wanting to install a hardened seat for the intake, it is not necessary. A standard seat is used to bring seat height back for an intake (or exhaust) when it has been sunk into the head by doing too many valve jobs. Going to a larger intake valve allows the seat to sit farther out, and therefore, will be higher anyway.