To give a little background I recently had a timing chain let go and allow some valves to do a meet and greet with Mr. Piston. Got some new stock valves to put back in, lapped the new ones, vacuum tested without springs and wasn't getting a good seal with a couple on the exhaust side. Had my machinist grind the valve seats to ensure proper seal. Now my question is with with the valve seats on the exhaust side being ground down won't that change my engagement to the rocker? Essentially making the valve too long and prevent it from closing? I know they have hydraulic lifters on the tips of the rockers but how much travel will they take up? I was looking for pretruded stem length, like a measurement from the spring seat to the tip of the valve but couldn't find such spec in the manual. Any suggestions?