Question regarding 273 rocker shafts

[SgtLee511]

The 273 shafts appear to be the same as the hydraulic shafts on my 72 340, but the oiling holes are mutch larger on the 340, can the
340 shafts be used with the adjustable rockers, I was just speculating that there would be better oiling with bigger holes, or should i stick with the 273 shafts?

 

[toolmanmike]

Use the shafts that go with the rockers. They are different (obviously) than the hydraulic lifter shafts.

 

[SgtLee511]

Use the shafts that go with the rockers. They are different (obviously) than the hydraulic lifter shafts.

Thank you

 

[krazykuda]

If I remember correctly the 273 rocker shafts have the banana grooves in them...

 

[perfacar]

you can cut banana grooves in 340, shafts. they will work. done that already.

 

[Rocket]

The one other difference in shafts for the mechanical rocker arm shafts aside from the banana groove is a second oiling hole for pushrod cup oiling to better ensure adequate lubrication and cooling for the ball and cup. If you look closely the pushrod oiling hole is larger than the hole in the banana groove.

 

[toolmanmike]

If I remember correctly the 273 rocker shafts have the banana grooves in them...

I think only 340 shafts are banana grooved.

 

[Rocket]

Only Engines that came with adjustable rocker arms from the factory came stock with the banana grooved shafts. The 273, perhaps not all of them were equipped with adjustable rockers, and the 340 6 pack engine came with adjustable rocker arms. Stock stamped hydraulic non adjustable Rocker Arms are designed differently and do not require grooved shafts.