>For those who maybe interested .....this engine is the Least desirable of
>the 215's available. This is the 1961 Old's F-85 block. The extra head
>bolt on the bottom side of the cylinder you would think was an improvement,
>but it was actually a problem with blowing head gaskets....because the walls
>are so thin there.
I have several Buick and Rover engines and a friend races a
stroker Olds. I'm not sure what you mean by this. The boss is
there on both Buick and Olds blocks, it's just not tapped on the
Buick version. The mating surface between the heads and the
block is the same. I have heard that the Buick 215 and Rover
V8's with 5 head bolts have a problem with sealing because
the fifth bolt (the one opposite to where the sixth bolt would be),
tends to load the head gasket unevenly. In the Olds, this isn't a
problem because the sixth bolt evens out the load (the bolt pattern
is symmetric). Later Rover V8's and the Buick 300 went with four
bolts around the cylinder and don't seem to have this problem.
RPI recommends torquing the fifth bolt to half spec and securing
with loctite to minimize the uneven loading.
>Best block for this engine are the late 80's and on Rover blocks because
>they made some improvements in the block's rigidity, and main cap
>alignments...
Yes, the Rover blocks got additional block stiffening ribs and
the very latest engines (4.0L and 4.6L) got cross bolted mains.
The Buick and Olds engines do have stronger bores because the
block was poured around the sleeves. The rejection rate for this
method was unfortunately high but the end product is stronger
than the Rover drop-in sleeves. I have heard that Rover had a
problem with some sleeves coming loose.
In practice, I've not seen any problems that could be attributed
to a weak block in standard or stroked form. I have seen trouble
with sleeved blocks though. For my stroker project, I decided to
go with a Rover 3.9L block. It has the larger bore and with a Buick
300 crank, should be 290+ cubes. Also, RPI claims the bolts
in the 2 bolt mains are undersized and can allow the main caps to
walk. The fix is ARP main studs which is what I used on my Buick
215 and plan to use on the Rover stroker.
Later,
Dan Jones
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