Well I decided to do some work on my 22r.I decided to change timing chain, valve seals, and new header.Well when changing the valve seal on the exhaust side piston 3 and 4 the valve guides where broken and the valves bent. Now I'm going to buy new exhaust valves and guides.My question is do I need to replace the valve seats as well?I'm not doing any major valve or head job I just want to get her back together with stock size valves.