273 banana groove rocker shafts

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Strokedcuda67

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I have read several posts about this and all seem to have different advice so I apologize about bringing this up again. I have a 340 with edelbrock heads and what I believe to be 273 adjustable rockers with the banana groove shafts. I have always heard to orientate the groove on the shaft to your left side notch facing down. Then I read that this may not be correct and some shafts were not assembled that way. When I place the shaft with the groove on the left side notch down my oiling holes face towards the engine and I have read that they should face towards the valve spring. Also I have read that the banana grooves should face up and then in another article they should face down. I am so confused.

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The notches are face down and to the front on the drivers and Rear on passengers.

Jake
If I position the notches that way the oil holes face towards the engine and everyone says to face the towards the valve spring. I think many are confused by just trusting the notch orientation
 
I have read several posts about this and all seem to have different advice so I apologize about bringing this up again. I have a 340 with edelbrock heads and what I believe to be 273 adjustable rockers with the banana groove shafts. I have always heard to orientate the groove on the shaft to your left side notch facing down. Then I read that this may not be correct and some shafts were not assembled that way. When I place the shaft with the groove on the left side notch down my oiling holes face towards the engine and I have read that they should face towards the valve spring. Also I have read that the banana grooves should face up and then in another article they should face down. I am so confused.

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I always run the grooves down, that’s where the load is. Everything is pushing up. I never paided much attention to the holes. With the notch on the left side of the head facing down the hole will be in the correct place.
 
I always run the grooves down, that’s where the load is. Everything is pushing up. I never paided much attention to the holes. With the notch on the left side of the head facing down the hole will be in the correct place.
I always run the grooves down, that’s where the load is. Everything is pushing up. I never paided much attention to the holes. With the notch on the left side of the head facing down the hole will be in the correct place.
that would position the small oil holes facing the engine side. If that is correct I am all for it, but everything I have read says the small oil holes need to face the valve spring
 
The shafts you have are the stock 273 shafts. You have two oiling holes, one in the banana groove to spread the oil on the load surface and a second oil hole for the adjuster and pushrods.

The grooves face down at about the 6:30 position or slightly towards the valve springs and the second hole is towards the inside of the engine.

As mentioned above in a previous reply above if you install the small notch in the end of the shaft facing down to the front on the drivers side and towards the back on the passenger side. This is the orientation outlined in the factory service manual. When installed this way you will end up with the banana grooves facing down for the load and the second oil hole for the pushrod towards the pushrods.
 
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Or the op can stop asking our opinion and put them on as per "I read they go this way". Good luck!
 
I have a set of 273 rocker shats with no banana grooves.

Does anyone know if some stock 273 rocker shafts came without banana grooves?
 
As mentioned above in a previous reply above if you install the small notch in the end of the shaft facing down to the front on the drivers side and towards the back on the passenger side. This is the orientation outlined in the factory service manual. When installed this way you will end up with the banana grooves facing down for the load and the second oil hole for the pushrod towards the pushrods.


This^^^.
 
Or the op can stop asking our opinion and put them on as per "I read they go this way". Good luck!
Seeing how some op don’t get it, it it’s not what they want to hear it’s like beating ur head against the wall. Put them on the way it makes u feel better.Yes lots of shafts never had the banana grooves. Kim
 
The shafts you have are the stock 273 shafts. You have two oiling holes, one in the banana groove to spread the oil on the load surface and a second oil hole for the adjuster and pushrods.

The grooves face down at about the 6:30 position or slightly towards the valve springs and the second hole is towards the inside of the engine.

As mentioned above in a previous reply above if you install the small notch in the end of the shaft facing down to the front on the drivers side and towards the back on the passenger side. This is the orientation outlined in the factory service manual. When installed this way you will end up with the banana grooves facing down for the load and the second oil hole for the pushrod towards the pushrods.
I appreciate your clear answer. Most posts on the subject say face the oil hole towards the exhaust and if I positioned it that way my notch on the end of the shaft is pointed upwards. If I install the grooved hole outwards towards the exhaust and the single hole towards the engine the notch on the end of the shaft is oriented correctly facing down. I just wanted to make sure I have them correct, don’t want to destroy a fresh engine I have sunk so much time and Monet into.
Seeing how some op don’t get it, it it’s not what they want to hear it’s like beating ur head against the wall. Put them on the way it makes u feel better.Yes lots of shafts never had the banana grooves. Kim

Seeing how some op don’t get it, it it’s not what they want to hear it’s like beating ur head against the wall. Put them on the way it makes u feel better.Yes lots of shafts never had the banana grooves. Kim
I want to say thanks to rocket for explaining the orientation to me in a way that made sense. As I explained in my 1st post there are many articles in this forum and others that contradict each other. Most people including many gold members of this forum just assume that the notches will dictate which way the shaft is placed and I have found 2 different articles where people have suggested you cannot go off of the notch orientation because some were wrong from the factory. Many threads say the oil hole goes towards the valve spring and if I orientated my small oil hole that direction it would be wrong. Not many articles deal with the banana groove shafts and I was confused on that. I think I understand that the oil hole would face the engine centerline and the banana groove would face the exhaust side. It appears that the oil hole will be close to the small hole in the rocker arm that distributes oil to the rocker arm tip on the valve spring. Again I appreciate rocket for explaining that to me. I don’t want to trust someone that just thinks the shaft notch dictates the position when I have sunk so much time and money in this build
 
good thinking
and if you are a visual person the photo showing the bolt angles and the angel of the center of the shaft facing down is also correct (spellcheck missed that one)
THERE ARE ALSO AFTERMARKET SHAFTS THAT ARE JUST WRONG
 
Good on ya for questioning it, better to be safe than sorry. I always went under the assumption of notches down and to the left. Never looked "beyond" that. So far it hasn't bit me in the arse.
There is a pic on here somewhere that has straws in the holes of the rocker shafts to demonstrate oil hole orientation.
 
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