I was speaking to a local Rover Engine Builder, who has years of
experience building Rover/P76 engines.
Initially they used to drill the block to tap the oil journal, when using
non-P76 heads on a P76 block.
Then they noticed the small hole on the underside of the Rover rocker arm
where it meets the pushrod. Since then, all they do is use the original
P76 hollow pushrods, and the conventional Rover Rocker gear. The
principle is that there is a lot of oil being blown around from the
interface between the pushrod and rocker arm (as with the original P76
arrangement), and the small hole allows reverse flow (relative to the
conventional Rover oil flow direction) through the rocker arm to the
rocker shaft. To get the appropriate pre-load the mill approximately
0.060" off the Rover rocker shaft pedestals.Said they have done it for
years without a problem.
I can only report it at face value.
Peter Kent.
Greg wrote:
Hi group,
I've mulled this problem over for quite a while and after talking
with a BUNCH of different people, I've got some OPINIONS on how it can be
done.
1) The BEST way (Also the MOST expensive). Order a set of Roller Rockers
from T&D Machine in Carson City Nevada. They have sets for the 215 in
various ratios and allow for oiling through hollow pushrods. These have
to
be used with lifters (cam followers) for the 70-81 Buick 350. I think 77
up
Buick V6 lifters are identical. The Rockers and heavy duty shafts are
around $500US a set. They aint cheap! But, one might be able to reuse
the
stock P76 pushrods as well.
2) Another way (A lot cheaper). Have fabricated a pair of rocker shafts
the
same diameter as the 70- 81 Buick 350 or late Buick V6 and use the stamped
steel rocker arms, also from the 350 and V6. The rocker arms are held in
place with teflon buttons and have a 1.55 ratio. They are non-adjustable.
I think TA Performance in Arizona can do this. Of course, the rocker
stands
would require honing to open them up. Don't know how much this would
weaken
them.
3) The CHEAP way. Tap a "Tee" fitting into the oil pressure switch outlet
on the front cover. Run an oil line to both heads. Drill a hole in the
heads just below the rocker covers and tap a fitting through it. Tap and
thread the rocker shafts at the front and attach an elbow fitting to that
and connect it all up. Sounds flakey... BUT, it works. I got that tidbit
from a Buick v8 guy. He'd built up a late Buick 455 with the better
flowing
67 430 heads. The problem is exactly the same... only on one side. 430
heads oiled through the block while the 455 oils through the pushrods.
Weird thing is, the 455 block has the block oil passage, only on ONE side!
Anyway, they had to do what I've described to make the 430 head work on
the
right side of the block. Worked great! He even sent me a picture of it.
Seeing is believing. Knarly, but real neat! He has 8000 miles on the
motor
with no problems.
Anyway, that's my two cents on that. Oh yeah, thanks a bunch for
the encouragement Lar! Your opinion is appreciated. :-)
Greg
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