Re: The Second Packard "Twin Six"

Posted by PackardV12fan On 2008/9/23 9:09:14

You are confusing VALVE lay-outs with BORE lay-outs.

The "nail-head" Buick blocks YOU think that I think I was referring to, were of conventional design, in that the cyl. bores were at right angles to the top of the block, like most internal combustion engines. This makes for MUCH easier machinging and and service than having an ANGLE between the BORE and the BLOCK.

Re-boring most production automotive-engines involves a relatively simple "set up" for the boring bore. Bolt it down, start it up, and down goes the cutting tool.

Re-boring a Packard Twelve is impossible with most production boring machines. Can't be done. You have to have either a very special Packard-unique boring plate adapter, or (I am told - never actually seen one, much less operated one) a boring bar rig that CAN bore at angles.