Lynn, Tony, Darrin, can I ask why you chose adjustable lifters in the first place? I've never understood the logic on V8 flatheads, because you can't ACCESS them in service. They make some sense for in-line flatheads, where they equate to adjustable tappets on OHV motors, but even so they still come at the cost of greatly increased weight requiring substantially heavier valve springs.
Tony Baker mentioned a while back: "Decision between solid and adjustable lifters was made for me, because the cam I am using has been ground for 'street' use. Adjusting the Johnson lifters is a PIG of a job. I am minus several portions of skin as a testament to that fact. No swear words were uttered, although they were thought! Even with the correct lifter adjustment tools, and a 7/16 open ended spanner I ground considerably thinner than originally intended, still a painfully slow process."
In fact Tony was misinformed. Even the wildest cam does not require adjustable lifters. If the base circle is reduced beyond the reach of the stock valve, the standard solution is to use SB Chev valves ground to the appropriate length, with 8BA lifters to suit the parallel stem valve, and replacement valve springs of the required length and tension (or suitably shimmed stock valve springs).
Tony also mentioned the potential risk with adjustable lifters: "I hope to christ they don't re-adjust themselves during operation. Not aware of any instances of this occuring, and certainly don't wish to be the first. Thought about putting a dob of threadlocker on each. Don't know that would be a good idea. Does that stuff still work in the heat of an engines internals?"
A quick search of the net would indicate this risk is real, eg. following exchange in Ford Barn forum:
"I put a set of adjustable lifters in one of my 1940 Ford engines. Started the car and it sounded great. Two days later lifter noise has increased and the more I drive it the louder it gets. Is the red Loctite stuff the only answer for this problem or is there something else? Lifter screws are very tight to turn until you screw them way down to their bottom for the adjustments. Johnson lifters"
Reply: "toss them in the trash and have the valves set the right way, valves stem ground till the right clearance is achived, ive had more trouble over the last 50 yrs with those worthless adjustables, no matter who makes them"
That's exactly the advice Alex received from his engine builders.
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One of the original Australian CMP hunters.
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