Features

• Machine valve spring seats for proper installed spring height and spring cup fitment
• Hardened pilots fit all 3/8" and 1/2" hand drills
• Cutter bodies and pilots are interchangeable
• Cutter: Cuts spring seat 0.550" ID x 1.180" OD
• The M-Eight cylinder head material under the valvespring seat pocket to the top side of the exhaust port is fairly thin even more so on ported cylinder heads.

Specs