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Discussion Starter · #1 ·
Ok, that looks odd, let me rephrase,” questions about 47 heads, “

just tinkering today, so trying to clean engine, took valve Covers off and some thing looks askew, one rocker nut is a standard kind, rest have a locking internal nut with allen hole in , and there are. Pushrod guide plates, cannot find anything in the service manual about them, are they because of the different locking nuts? Or is it just normal??
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Ok, that looks odd, let me rephrase,” questions about 47 heads, “

just tinkering today, so trying to clean engine, took valve Covers off and some thing looks askew, one rocker nut is a standard kind, rest have a locking internal nut with allen hole in , and there are. Pushrod guide plates, cannot find anything in the service manual about them, are they because of the different locking nuts? Or is it just normal?? View attachment 159201

Those are called polylocks and not factory. Pushrod guide plates are.

A polylock features a threaded body and a set screw. The body screws over the stud and holds the rocker arm in place. Then, the set screw is tightened down against the stud. This locks the body in place.
Polylocks make adjusting you valvetrain much easier. They are useful when setting preload on hydraulic lifters. They are required to set valve lash on solid lifters. Polylocks also come in various lengths.

Polylock Adjustment Procedure
Follow the steps below to adjust your polylocks AFTER you have adjusted the preload on your lifters.
  1. Set the valve lash or lifter preload by turning the outer hex nut (polylock body), set screw backed off.
  2. Once valve lash/lifter preload has been adjusted, hold a wrench on the polylock nut to keep it from turning, and screw in the allen set screw snug onto the rocker am stud.
  3. Loosen the outer hex nut approx. 1/16 of a turn.
  4. Tighten down the set screw.
  5. Then tighten BOTH the screw and nut together until they jam and become much harder to turn (25-30 ft.-lbs).
  6. The outer hex nut should be back in the same place it was before you loosened it. Recheck your lash setting. If it's off, loosen up the polylock and try again.

Note the picture below. The allen screw is even with the top of the polylock body. Your stick above the body, too much in my opinion. The set screws are not very long and you probably have a minimum of threads inserted into the body - which can cause then to fall out of adjustment more quickly or become stripped out when you go to tighten/snug the allen screw down. You can remedy this by using a hardened washer under the polylock and on top of the rocker arm ball to raise the height of the polylock and thus allow the allen set screw to seat deeper into the polylock body.

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Discussion Starter · #4 ·
I actually have them on my lt1 in my jag, but they are on full roller rockers, had I seen them in standard rockers before, plus they are mix and match, removed other valve cover and only 3 are that kind, rest are stock
 

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Sounds like someone had problems with the original nuts staying put and added the poly-locks as needed. It won't hurt a thing to have them mixed, but I'd do all poly-locks...they are just good insurance. Both my recent builds have them and my '67 had them before tear-down and will have them again.
 

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those heads fit 1969 350 265 hp they have 1.96/1.66 valves . the lock nuts arent a big problem probably replaced the originals at some time but didnt have a full set or the originals were backing off , so if those heads are on you 400 in your goat i'd consider looking for a better set of heads if it were up to me
 

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Discussion Starter · #7 ·
Engine is just a 350, nothing special, in a lemans, will be a cruiser, not a race car, did the performance thing on the lt1, heads, cam, intake throttle body, injectors, etc, this needs to be a bit more sedate, so the wife can drive it! :)
 
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