Reworking the 273 Adjustable Rockers

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Okay now you guys made me get up off my bed leave my coffee go out to the garage get an old busted rocker shaft and pull out a flat file and use the edge of it. And it was kind of like I thought. Because of the roundness of the shaft using a straight edge it would get deeper in the center naturally. I think using something round would make it even deeper in the center? Also it's before 7 in the morning here on the West Coast and I'm not firing up my grinder with my wife still sleeping LOL to see what the round wheel would do...
IMG_20190303_065733.jpg
 
With hole in center of groove, it will be the deepest part, especially if groove is cut with round disc.
Dimensions on factory grooves would be interesting to see.
You dont have to fire up grinder in the bedroom....
j par said:
Okay now you guys made me get up off my bed leave my coffee go out to the garage get an old busted rocker shaft and pull out a flat file and use the edge of it. And it was kind of like I thought. Because of the roundness of the shaft using a straight edge it would get deeper in the center naturally. I think using something round would make it even deeper in the center? Also it's before 7 in the morning here on the West Coast and I'm not firing up my grinder with my wife still sleeping LOL to see what the round wheel would do...
View attachment 1715297636
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4spdragtop said:
With hole in center of groove, it will be the deepest part, especially if groove is cut with round disc.
Dimensions on factory grooves would be interesting to see.
You dont have to fire up grinder in the bedroom....
Click to expand...
Now I think this would be easily solved if a member had a set with the grooves and laid straight edge in a factory Groove and see if it's flat or if it's concave?
 
That file job actually looks pretty close; the grooves do taper. That may explain why they were angled.... Simplified machining.
 
j par said:
Okay now you guys made me get up off my bed leave my coffee go out to the garage get an old busted rocker shaft and pull out a flat file and use the edge of it. And it was kind of like I thought. Because of the roundness of the shaft using a straight edge it would get deeper in the center naturally. I think using something round would make it even deeper in the center? Also it's before 7 in the morning here on the West Coast and I'm not firing up my grinder with my wife still sleeping LOL to see what the round wheel would do...
View attachment 1715297636
Click to expand...
Also that picture is available because jab sent me a replacement shaft for that broken one so I could file on it like that..
 
If you're making your rocker arm shafts for the adjustable rocker arms don't forget to put the second hole in the shaft. You can see it in that picture that is posted showing the slots.
According to Yellow Rose those holes from the factory are in the wrong spot so this is a perfect time to line them up where you want them to be and then drill.
 
Jadaharabi said:
If you're making your rocker arm shafts for the adjustable rocker arms don't forget to put the second hole in the shaft. You can see it in that picture that is posted showing the slots.
According to Yellow Rose those holes from the factory are in the wrong spot so this is a perfect time to line them up where you want them to be and then drill.
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Yellow who?....
 
j par said:
I went up a few and seen yellow rose and I was thinking holy crap that stinkers back! Then I noticed the date LOL...
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Of you miss me that much you can always call me. You have my phone number. Now I'm off to the shop. For the first time in a month.
 
Jadaharabi said:
If you're making your rocker arm shafts for the adjustable rocker arms don't forget to put the second hole in the shaft. You can see it in that picture that is posted showing the slots.
According to Yellow Rose those holes from the factory are in the wrong spot so this is a perfect time to line them up where you want them to be and then drill.
Click to expand...
Interesting.
4spdragtop said:
Pics I pulled from fabo threads. The grooves dont appear be centered with hole.

View attachment 1715297653

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FWIW. These are the rocker shafts I got from Hughes
upload_2019-3-24_20-29-58.png


Needed to replace these. Not sure what they were meant for or came from but didn't work out. :eek:

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MVC-496F.JPG
 
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Could have been the oil pickup not being against the bottom of the pan for the first year or so.
But this is from the Taylor and Hofer How to Rebuild Your Small Block Mopar.
upload_2019-3-24_20-37-51.png


Feel free to disagree. All I had at the time was that and the shop manuals.
 
Mattax said:
Could have been the oil pickup not being against the bottom of the pan for the first year or so.
But this is from the Taylor and Hofer How to Rebuild Your Small Block Mopar.
View attachment 1715308749

Feel free to disagree. All I had at the time was that and the shop manuals.
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The notch is left and down with you standing at the side of the engine, for the shaft pictured.
 
Mattax said:
Could have been the oil pickup not being against the bottom of the pan for the first year or so.
But this is from the Taylor and Hofer How to Rebuild Your Small Block Mopar.
View attachment 1715308749

Feel free to disagree. All I had at the time was that and the shop manuals.
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LOL... the wear from the stamped rockers in that pix is on the under side of the shaft where they press upwards on the shaft.... and where the holes are shown in that pix. Obviously wrong text with that pix. No wonder folks get it wrong from time to time if that error is out there in print.
Jadaharabi said:
If you're making your rocker arm shafts for the adjustable rocker arms don't forget to put the second hole in the shaft. You can see it in that picture that is posted showing the slots.
According to Yellow Rose those holes from the factory are in the wrong spot so this is a perfect time to line them up where you want them to be and then drill.
Click to expand...
I recall that thread info... and wonder about 1 thing. These shafts don't see much pressure, and are not filled to the brim with oil at the lower RPM's. YR was wanting to fix the high RPM starvation of the cups where he ran his stuff, and lining up the shaft holes where they could intersect the rocker cup oiling holes at some point in their motion. But, for extended low RPM operation, I am not sure it makes any difference.
 
Mattax said:
The '67 Plymoouth FSM says the notch should face the centerline of the engine, front for left bank, rear for right. That matches what you're saying and showing.
Now you got me wondering what I did when I put the Hughes shafts in. Time to dig through my notes.
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when I seen those pictures they made me think twice to LOL. I'm sure I got it right, that crap too expensive...
 
j par said:
when I seen those pictures they made me think twice to LOL. I'm sure I got it right, that crap too expensive...
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Tell me about it. Had to send those rockers out to get bushed. If I don't have notes I'm going to have to go through some stuff at the garage! Didn't take many photos back then - it was either film or a floppy disk camara. Very conservative on picture taking. LOL
 
Mattax said:
Tell me about it. Had to send those rockers out to get bushed. If I don't have notes I'm going to have to go through some stuff at the garage! Didn't take many photos back then - it was either film or a floppy disk camara. Very conservative on picture taking. LOL
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I saved for 2 years wanting roller rockers and when I bought the Hughes stuff I went all-in, rockers hold Downs shafts the whole nine yards...
 
I had great experience with the Crane ductile rockers on the previous engine. When I made the discovery on the current engine, that was winter 2009-10. Crane stuff wasnt available. Rocker Arm Specialist in Calif. $200 plus 12 for shipping. looking through the reciepts - those were some expensive years
 
nm9stheham said:
I recall that thread info... and wonder about 1 thing. These shafts don't see much pressure, and are not filled to the brim with oil at the lower RPM's. YR was wanting to fix the high RPM starvation of the cups where he ran his stuff, and lining up the shaft holes where they could intersect the rocker cup oiling holes at some point in their motion. But, for extended low RPM operation, I am not sure it makes any difference.
Click to expand...
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From the factory they use a timed port in #2 and #4 cam bearing. Nowhere has it ever been said that they are only partially filled. As rpm increases they have more pressure as does the rest of the oil passages.
 
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