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How far do the rocker arms move on a 360/401? I replaced my intake manifold and went 2bbl the other day and while the valve covers were off I noticed no deeply dipped rocker arms. All my past experience is with GM engines and normally there's at least one valve fully open and dipped towards the head a fair ways. I suspect a worn out cam which I've been suspicious of anyway.
How far does the valve side of the rocker arm move? What is normal?
I haven't had a chance to put the vacuum gauge on it yet but it runs waaaay better than with the 4bbl
1964 Triumph TR4 with 1964 Olds 215 heart transplant
1977 Wagoneer
2009 BMW GS1200
Removing the valve covers isn't required for that, so I am assuming you were going off the positions of the lifters?
AMC (along with Ford) uses 1.6 ratio rockers, so the rockers have more throw than a GM which uses 1.5 ratio. So you get more valve travel for a given amount of cam lift.
The lifters are hydraulic, so they bleed down somewhat when the engine is off and you likely won't see one fully open unless you have a stuck lifter. The only engines - regardless of make - that would keep a valve fully open when off are engines with solid lifters. If you want to watch what's really going on, crank the engine over with the cover off. It will make a bit of a mess with oil flinging around, but it's not terrible. I actually adjust the lash on my LT1 with the engine running since it makes for a closer/better lash setting than doing it with the engine off and going 1/4 turn on the base circle of the cam.
Edit: if you're worried about a wiped cam lobe, you'd definitely hear it before you noticed anything with the way it runs. Lots of clacking because of the increased clearance in the valvetrain geometry. Cams,lifters and rockers will usually let you know well in advance that something is up. Bad valvetrain parts make a racket. You can also pull your oil filter and use a filter cutter to peel it open and look for metal. That's a telltale way short of sending an oil sample to blackstone.
They make clip o. Plugs to prevent oil.splash, ive got a set i use to use on old school chevy 350's, and u are right if u have cam wear that bad u will hear the clatter, and blackstone is a good way to detect a problem, but you need to start doing it from. New or overhaul and every oil change, because it monitors oil trend changes and not designed for 1 time checks, fleet operators, airlines, aircraft owners do it because a current 280 hp aircraft costs around 80-90 grand not i ncluding install. So with trend monitoring you can see a pro lem early