[6pack] Compression boost

[Joseph Grant]

This whole thread about compression ratios is quite interesting.  I have
several questions for you all:

You talk about increasing the ratios to 9.0, 9.5, etc.  Given head 'x', how
is the compression ratio calculated?  What backs the statement made that by
milling the head 'x' or 'y' amount, the ratio is exactly 9.0 or 9.5 or
whatever?  I realize machine shops know what they are doing, but there are
many factors that will affect the final number.  Also, if the engine has
been at one point in it's lifetime been milled or for that matter, the block
milled also how is that calculated into the equation to know exactly what
ratio will be at the end of the machining process?

For the guys that have had this done, how do you know for certain the ratio
number is correct?  I am not doubting your numbers, just asking how the
numbers are calculated...

Joe
'72 TR6 - CC77169
http://www.bowtie6.com/