Exhaust valve guide bronze: Cosworth YB
 
Colsibro. Stem guide clearance 0.055-0.077mm.
Ford Cosworth YB 16v Turbo
Application:
Ford Sierra RS Cosworth 3 door 1986-1987
Ford Sierra Cosworth RS500 1987
Ford Sierra Sapphire RS Cosworth 2wd 1988-1989
Ford Sierra Sapphire RS Cosworth 4wd 1990-1992
Ford Escort RS Cosworth 4wd T34 1992-06/1994
Ford Escort RS Cosworth 4wd T25 06/1994-1996
 
YBVALVEGUIDE