ikeybmg

or show ma a decent link to a calculator. i have a 347, vic jr heads, 2.05 1.60 valves, 210cc, 70cc combustion chamber. ross forged flat tops. anything else im leaving out that ill need to know? thanks guys.

myshifter

how far is piston below the deck and head gasket thickness and the bore of the HEADGASKET not the block

randy78045

wouldnt it be easier to just use a compression tester? [X(]

tinman

No, that is useful for trying to figure out damage to engine.
there no way in H that will figure compression ratio now or ever......

FiveLiterRiceEater

9.5987253:1

r.barn

lets get technical.............

compression ratio is the ratio between the volume of
the cylinder and combustion chamber when the piston
is at BDC vs. that same volume at TDC.

You need the following engine information

C ..... Combustion chamber volume
G ..... Compressed head gasket volume
D ..... Piston/Deck height
P ..... Piston dish volume
V ..... Cylinder volume

so your compression ratio is ratio between

V+D+G+C+P : D+G+C+P


btw: got all that out of following book, very good reading
http://www.amazon.com/gp/product/193...v=glance&n=130

randy78045

I'm confused...

FiveLiterRiceEater

i learned all of this in school once..



well i would have learned it, had i not been reading a mustang magazine in my general motors class

ikeybmg

yea im gonna get it tested. i was just wondering what it would be roughly. i cant find i good calculator on here.

ikeybmg

im coming up with around 11.3:1. thats pretty high so s/c is out of the question huh? is that a good number for n/a ya think?