Inliners International Forums General Discussion Engines Hardened Valve Seat Inserts and unleaded fuel . . .

Yes in a stock configuration I see no need to. In my case yes its on a "test engine" but if I drop the $ into this head (since it needed it with multiple sunk valves) I can reuse it with the turbocharged engine instead of doing work on 2 separate heads.

But like others have said on a high RPM, High load engine its may be worth your time and $.