273 commando questions

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fireguyfire

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Just reassembling the matching number 273 commando engine in my 67 barracuda. I had it machined.
When I bought the car last fall it had been sitting for years and someone had broken into the barn it was stored in and stole the air cleaner, rocker covers, and the rocker valve assemblies years ago.

I’ve sourced replacements on all of those missing parts, and I have a couple of questions about the rocker assembly as I have one side all apart and cleaned and ready to be re assembled and installed.
I’m guessing the rockers shafts have to go in a certain direction as there is a small half moon shaped notch at one end me and I’m guessing that’s an orientation mark? I also see that there are small oiling holes on one side of the shaft under each rocker.
Obviously I want to get everything installed correctly so can someone help me out with should the 1/2 moon notch on the rocker shaft go to the front, or the rear of the head? And should the small rocker oiling holes on one side of the shaft face the inside or the outside of the head?

Thanks!
 
 
Another related question for setting the valves once installed. In the FSM and online it says to set them hot, but of course I’m reassembling the engine after a full rebuild.
I’m guessing setting the valves to the same specs cold will be good enough for a start to break in the engine, and then reset them hot to those same specs in the future.
 
And again, my engine is the 273 commando; are the valve lash settings different than on a regular 273? I know the cam durations etc were quite different.
 
And again, my engine is the 273 commando; are the valve lash settings different than on a regular 273? I know the cam durations etc were quite different.
No difference. The lift and duration weren't all that different between the 2.
 
Yes, ball/cup. Only differences were cosmetics, dual point distributor, camshaft and slightly stiffer valve springs.
Be careful with the notches on rocker shafts, MOST but not all face front of engine and down. Think of it this way when hanging over a fender "down and to the left". Again this is for MOST. I believe the bottom oiling holes face the springs.
Are 273 and 273 commando pushrods the same?
 
Are 273 and 273 commando pushrods the same?
Yes. Pistons and cam are different. All the rest is the same except the 4 barrel, intake, air cleaner, dual point, and valve covers. Valve springs? I would have to check that.
 
Thanks for all of the info gents. See 273 pushrods for solid lifters easily available? I do see them for hydraulic lifters, but of course I have solid ones.
 
Thanks for all of the info gents. See 273 pushrods for solid lifters easily available? I do see them for hydraulic lifters, but of course I have solid ones.
A wanted ad might be the way to go.
 
I’m guessing the rockers shafts have to go in a certain direction as there is a small half moon shaped notch at one end me and I’m guessing that’s an orientation mark? I also see that there are small oiling holes on one side of the shaft under each rocker.
Obviously I want to get everything installed correctly so can someone help me out with should the 1/2 moon notch on the rocker shaft go to the front, or the rear of the head? And should the small rocker oiling holes on one side of the shaft face the inside or the outside of the head?

My '65 Commando shafts also had the half moon shapes at one end on each shaft (instead of a notch). Those should point down to engine center line and to the rear on pass side, to the front on drivers side. Using this orientation (per service manual), the oiling holes on the factory shafts pointed towards the pushrods.
 
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