Perfect timing to read this. I have LS heads on one side of my bench (8mm I think) and Indy LAX heads on the other side (5/16 I think).
Hughes has 8mm, but not 5/16". They said 8mm and 5/16" are interchangeable. Really?
2.5 thousands clearance difference on a valve to valve guide measurement is a big deal. Guide needs to be sized properly for the valve stem. Guides and stems need to be measured sized properly to give adequate clearance period. As to Hughes you would think they would have learned their lesson with the first round of EQ's they sold that seized valves.Hughes has 8mm, but not 5/16". They said 8mm and 5/16" are interchangeable. Really?
This ^^^I had 8mm valves put in my magnum heads and my machinist had to size all the guides. He said it didnt take much, but they did have to be sized.
Ive bought 3 sets of EQs for magnums, 1st set bare, 2nd and 3rd supposed " bolt on and go" right from EQ. the most recent was the only set of the 3 that I wanted with a magnum intake pattern. I put em in my wife's 360 Durango and didn't make 6 miles..... Seized stems. Needless to say I wasn't happy.2.5 thousands clearance difference on a valve to valve guide measurement is a big deal. Guide needs to be sized properly for the valve stem. Guides and stems need to be measured sized properly to give adequate clearance period. As to Hughes you would think they would have learned their lesson with the first round of EQ's they sold that seized valves.