>Cam bearings: if the cam holes are out of round... you have no choice but
>to align bore the block for the Spitfire bearings.
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Unless I'm missing or forgetting something there isn't any way to "align
bore" the cam bearings in a TR block, or any block with 'fixed' bearing
holes. I hope the originator of this doesn't think I'm nitpicking, as that
is not my intent, just trying to clear things up a bit. The reason is that
to do an align bore (which is basically to make sure that the bores are
aligned or concentric), is to shave a small amount from the bottom of the
bearing caps so that now the bearing holes are slightly oval. That is to
say the "height" measurement, when bolted together, is less than the
"width" measurement. The bearing caps are then bolted to the block,
torqued to spec, and the "oval" holes are then bored, in line, to the
correct dimension making everything true and concentric. Without bearing
caps, I don't see any way this can be done as any additional boring to the
cam bearing holes will only make the hole larger (out of spec for the press
fit required, unless the bearings require a larger hole) and if that's the
case then boring the holes to the correct size for the bearing will allow
one to use bearings in a block not originally designed for them, which is
actually a better proposition anyway as it will allow higher cam bearing
loads without the fear of galling - steel on cast iron isn't really the
best of bearings surfaces, but it is cheaper to manufacture and "adequate",
but just, for street use :-)
Barry Schwartz (San Diego) bschwart@pacbell.net
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