Harland Sharp or Scorpion Roller Rockers

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   Mike can also source a shaft rocker system for earlier stud rocker heads, with different ratios, if required. He used one on POS1 to go 8000rpm, so it`s been tested!

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BBO UK Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Nut Joined: Feb/17/2020 Location: UK Status: Offline Points: 286	Post Options Post Reply Quote BBO UK Report Post Thanks(1) Quote Reply Posted: Mar/03/2024 at 7:00am
	Mike can also source a shaft rocker system for earlier stud rocker heads, with different ratios, if required. He used one on POS1 to go 8000rpm, so it`s been tested!

PHAT69AMX Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/07/2007 Location: West Virginia Status: Offline Points: 5918	Post Options Post Reply Quote PHAT69AMX Report Post Thanks(0) Quote Reply Posted: Mar/05/2024 at 3:25pm
	Keller - take a picture of it from the front strait on with a stock length pushrod in it so we can see the side view of a rocker arm and all with the cam on base circle and the valve closed.
	Link to a Short YouTube Burnout Video

nitro-express Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jan/20/2024 Location: Manitoba Canada Status: Offline Points: 71	Post Options Post Reply Quote nitro-express Report Post Thanks(0) Quote Reply Posted: Mar/09/2024 at 10:51am
	First; thanks for starting this thread. I'm new to discovering the nuances of the AMC V8 and recently acquired some post 73 heads and hadn't yet considered rocker options, other than bolting in a set of Ford 351W rockers, same 5/16 stud. The question at the core of this setup is the design limit on the 5/16 bolt. The bolt is likely the weak point due to its size. I also found reference to the rather small base on the rocker was a weak point as well. The Harland Sharps set uses a broader base on their pedestals to address that, and they list a limit of 350 lbs. on the open spring pressure. Scorpion does not have a spec listed on their set, so I contacted them and they came back with the same 350 lb at max lift but added a limit of .500 max cam lift as well. If you dig into the differences between the two, both use a different system to keep the rocker pairs witnessed. The Scorpion uses a U channel, and the pedestal is narrowed, whereas the H&S is not. The H&S system uses a pin between the trunnions to keep the rockers in alignment, and drills the center of the trunnion to accomplish that. IMHO that should not weaken the trunnion much if at all. I'll keep researching but so far I'd lean towards the H&S set. For my JRD (Junk Yard Dog) resurrection, I'll likely use the lightly worn Ford 351W rockers I have in my tickle trunk, and limit the open pressure to 250# and keep the lift to about .475 max. An option not mentioned is to add a stud girdle to the equation, that shares the load between the rockers. However that would require a design change to the 5/16 bolt. Always fun.