OK, I know this subject has probably been covered a thousand times in the past but I'm getting conflicting opinions.

Is it absolutely necessary to tube the block OR sleeve the lifter bores when converting an early style LA block to pushrod oiling?

I have a new (never used) Mopar 340 replacement / 59 degree R3 block, lifters with EDM oiling and T&D rockers.

My argument is-

If magnum blocks are 59 degree from the factory with hydraulic roller lifters and pushrod oiling with large holes intersecting the oil gallery, then why do you 'have to' bush a block when essentially I'm doing exactly the same?

PS The lifters are not uncovering the oil galley at any stage of travel.

Please help
Thanks in advance
Macka

Is it absolutely necessary to tube them... no.. but
it helps if you lose a lifter and you dump all the
oil pressure... on my LA block (416 in my Rampage)
I bushed them with a .060 hole in the bushings and
a .040 restriction in the PRs.. this is with a solid
roller with .640 lift at the valve.. it was within
.015 of uncovering the oil passage so I left the bushings
on the tall side just to make sure it didnt have a issue..
I'm running the EDM hole in the lifter for the street which
is .026 for that hole.. with all the little leaks you will
show lower oil pressure.. also this is with TD rockers...
all in all its a easier way to control oil losses

It has Zero to do with PR oiling. If you are not using a hydraulic lifter then you don't need all that oil at the lifter. And I'm not sure I wouldn't tube a hydraulic lifter deal and just drill a .060-.080 hole in the tube.

The lifter bores are horrible leaks. You need to stop the leak.

Cool. So with standard la timed oiling via the shafts, you have 16 less potential places for a leak to occur.

Thanks

I've had no issue with mag heads la block with edm solid lifters. No mods to the block 40psi at idle and well over 80psi through the traps.

That's what I have been told in the past!!