Re-facing valve seats in block: seat angle ?

[Special Coupe Frank]

If refacing the valve seats in the block ( for new, Stainless valves, etc. ), is it worth-while to go for a 3-angle grind, or just stay with the original-style single-angle ?

Block is a diamond-block with hardened seats on the exhausts.

Thanks !

Frank

 

[Ron W]

I went with 3-angle. I used at least 1/16 to 3/32 flat contact surface. Seems OK so far.
Ron W

 

[Patrick L.]

Original was a single angle ?


Three angles are needed and need to placed correctly for proper seat width [.060-.080" intake and .080-.090" exhaust]and location on valve face. There should be a lot of info in archives or search.

 

[jetmek]

3 angles are needed to get correct contact . My experience has been you seldom need to narrow it from bottom mainly need the 60 and 45