High compression blues.
Icon IC968. By their calculator, I have 10.9-1 compression.
Here's a problem, I cc'd a '75 or '76 440 with a set of OE 10.1:1 cast slugs in it, with the Mopar shim
[email protected]" & untouched 452 heads. It hit 9.98:1 when I was done.
Not a surprise as some of the late casting chambers were a tad bigger than the "906" era chambers by ~3cc. But I also measured a piston to deck ht. of .048", the .017"
gasket, and a chamber depth of ~.130".......that's .195" from crown to quench/squish surface.
1) the 440 6bbl slugs are .076" taller comp. distance.
2) the Trickflow heads quench/squish is .130" lower
3) That's .206" less room than You'd have w/10.1:1 slugs and You only had room for .195"!!!
4) You've only added .020"-.025" with the Felpro at best. that leaves You with ~.010" head to piston?!?!?!?
5) I think the 440 6bbl slugs were "under advertised" because.......a .030" over 440 needs 100.38cc total chamber vol to get 10.1:1, subtracting .076" @bore=-18.5cc +
the 4.4cc=14.1cc + ~3.5cc for the thicker gasket=-10.6cc that would calc. to 11.17:1.............but wait! the heads are down 10cc...a -20.6cc, thats 12.45:1!!!!!!
If someone sees a problem with this please point it out...........................................comp.ht. 10.1:1 1.991",....comp.ht. for the OP's 2.067"............................
