35 Valves and Guides

Trelpdx

Trelpdx

Senior Member
Guys,

8 years ago I bought the straight stem valves for my flathead. The valves have 2 grooves in the ends. Dumb question, but the keepers only can go in one of the two grooves. Which one?

Also, the just purchased the valve guide O-Ring for the intakes. These are like a sqare O-Ring about 1" in diameter. Where are these supposed to go?

Thanks much,
Peder
 
Im thinking the keeper will go in the groove closest to the valve head. The rubber o rings go in the groove around the intake valve guides. They seal the guide to the block.
 
Use the top groove. Spring pressures are low in flatheads, and can tolerate significantly higher pressures. The o-rings to which you refer go into the slots in the valve guides, intake only.
 
Ken, I'm not sure which type lifter you are planning to use, but I recall reading a post some time ago that mentioned you should not use the lifters originally used with mushroom type valves if you are converting to the later type straight stem valves. I think the logic was when using the later straight stem valves with the early style lifters, there would be too much force/pressure concentrated in a smaller area on top of the lifter and either cause more rapid wear at the contact point or possibly the stem could break through the top of the lifter. I just thought about this as I read your original post and wondered which type lifter you are planning to use? JM
 
I'm using new adjustable lifters with straight valves. Thanks guys for the info. Starting reassembly tomorrow.

Peder
 
By using the second groove (closest to the valve head) you will have higher seat pressure and less tendency to have any valve float. I would use this position if it were me.
 
You are using Chev valves. The position farthest from the head is the correct one for the keepers, the other is for the valve stem seal for the chev engine, totally useless for the flathead... Check this by assembling with out the spring and measuring the spring installed height... I like about 45 lb. spring pressure when valve is closed... Karl
 
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