1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 TAPPET BLOCK KIT

Part Number: 91-635

TAPPET BLOCK KIT - Part Number 91-635
Shovel Power Glide Tappet Kits are capable of the highest rpm a Harley can safely turn, at a valve lift of .700 and with the right valve springs, valves, cam and oil, etc. Shovel motors can have all the hydraulic benefits of the late Evolution style hydraulic system, by installing Jim's Shovel Power Glide Hydraulic Tappets. These kits will eliminate the total oil loss of old style hydraulic units. All of Jim's Billet Tappet Blocks are made from 7075-T651 with a tensile strength of 83,000 psi which is double the amount of 6061-T6 and almost triple the amount of cast tappet blocks. These tappet blocks are machined to the center line of the cam and hold to + .002 of an inch. Also, the bores are held perpendicular to the mounting flange to + .0002 of an inch. Billet Shovel Tappet Blocks with Power Glide Hydraulic Tappets. Fits Shovel Big Twins 53-84. Use 1/4" - 20 screws from late 1976 thru 1984) (Use 1/4" - 24 screws from 1953 thru early 1976) Do not use the early tapered 1/4" - 24 screws on these blocks unless you provide a counter sink for that style screw. These blocks are designed to accomodate a gross valve lift of .550 at the valves. This is about .350 at the tappets, leaving a clearance of .035 roller to block free play. Use with standard push rods OEM 17904-66 or equivalent. Kit contains the following: Two Shovel tappet blocks and four Shovel Power Glide Tappets which replaces the following: OEM NO. 18602-80A Rear block 18603-80A Front block 18522-53 Tappet with roller 17920-53A Hydraulic unit NoTE: These parts are not interchangeable with OEM. You must use these units in conjunction with each other.
Power Glide 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974

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