Another Valve Question

[Joe AZ]

I posted a question a couple of weeks ago regarding pulling the valves from my '40 block. It appeared that I had mushroom style valves, but they turned out to be '51-'53 valves.

My question is this: Every piece of literature I have on flatheads lists the valve stem diameter as .3115. My valves are checking out at .340.

Were the later valve stems a larger diameter?

Thanks, Joe

 

[Ronnie]

8 ba were 11/32 valves.

 

[Brian]

Going by your photo, you've got the later valve rotators. Valves, whilst appearing the same, actually have the keeper groove in a slightly different location to standard 8BA valves; still 11/32" dia stems though as Ronnie said

 

[Joe AZ]

Thanks for the clarification.
Joe

 

[Walt Dupont--Me.]

You have to use the 8BA guides with the 8BA valves. Walt

 

[Joe AZ]

You have to use the 8BA guides with the 8BA valves. Walt

Thanks Walt........guess I have the late model valve train in my '40 engine.
Joe