Edelbrock #8551 Head Bolt Kit is for 1965-90 Big-Block Chevrolet 396-454 Mark IV Engines with Edelbrock #50459, 60459, 60479, 60499, 60559, 61459, 61559, 79539, & 79559 Performer & RPM Cylinder Heads. Not for Stock Heads.
Edelbrock Spread-Bore Adapter