Topic: Valve seat angle vs. valve angle

[Jadahonda]

On a race engine... Someone say that the angle on the seat shall be 46 degrees and the angle of the valve 45 degrees. After starting the engine the valve and seat will mate and make a perfect match.

Othe say that both seat and valve shall have the same angle and also lap them to get a perfect seal.

Is there any opinion of whats the best of these 2 ways?

I have always cut them in 2 different angle with 1 degrees

Jan

[johno]

Gday mate !
The idea of two different angles ( interference angle) was originally developed for the art of mass produced engines.
The idea was to save time and money by not lapping in valves but still get an effective seal.   works OK  but I am happy to run the seats same angle,  with attention to detail its nice to hit the track with the valves exactly how you want them, full contact of seat for temp control and less change in valve clearance with big springs etc
ciao johno