Rocker Arm studs

    • Official Post

    Hi, I am looking to rebuild my heads next year. Is ARP 134-7104 https://arp-bolts.com/kits/arpkit-detail.php?RecordID=317

    the correct ones to use.

    I am aware that either guide plates or to chamfer the original stud holes is required to prevent the bosses from cracking.

    Thanks in advance Eddie

    Being as you are already aware of the differences in aftermarket studs, I do not see any issues with these.


    -Fred-

    65 Koupe early San Jose Phoenician Yellow 4 speed
    66 GT Koupe Dearborn Blue 4 speed
    66 KGT San Jose fastback pony interior Silver Frost 4 speed
    64 Falcon sedan delivery 289 4 speed
    65 Ranchero 289 4 speed
    66 Corvette roadster 427/425 4 speed

  • I would advise chamfering the bosses vs using guide plates.


    I have used guide plates with genuine HiPo heads a couple of times and everything worked well.


    However, most of the time, the pushrod guides cast in the head won’t permit the use of bolt on guide plates; resulting in binding pushrods at either the guide plates or the stock cast in holes, or both. To fix this you have to enlarge the guide plate slots which defeats their purpose, or drill out the slots in the head and make them round holes.


    I for one am unwilling to butcher a set of working HiPo heads in this way.


    I have had to deal with a HiPo head that had a small crack in the boss area. It was small but still was enough so the head would not hold coolant area pressure at the crack. Some red lock-tire on the rocker stud was all it took to seal up micro crack.



    Z

    • Official Post

    My use of guide plates on Hipo heads are when some of the original guide slots have been compromised. At that point I drill the original slots to a round hole. I prefer using the C9OX Ford guide plates as they are thinner and work well. Although they are thin, there are tabs bent down to give a good surface for the push rod to ride against. These were created by Ford for the early Muscle Parts program to enable people to use 351W heads on their small blocks. Ford serviced them through the normal parts channels at the time. Years later the same plates were offered through the Motorsports program. If you use the later Ford Motorsport ones, they appear identical with even the C9OX-B stampings, but some had improper spacing between the slots.


    -Fred-

    65 Koupe early San Jose Phoenician Yellow 4 speed
    66 GT Koupe Dearborn Blue 4 speed
    66 KGT San Jose fastback pony interior Silver Frost 4 speed
    64 Falcon sedan delivery 289 4 speed
    65 Ranchero 289 4 speed
    66 Corvette roadster 427/425 4 speed

Participate now!

Don’t have an account yet? Register yourself now and be a part of our community!