[Mojo]

I would like to know how to calculate compression ratio. My engine is a standard bore/stroke 1967 327using stock cast flat head aluminum alloy, 4 dimple pistons. My heads are stock '461 castings with a combustion chamber of reportably 62.076 cc's.
The AMA specs rate the 327/275 at 10.0:1. This engine originally had the '462 head which also has the 62.076 cc. Is this a valid compression ratio? What is the formula for calculating compression ratio? What octane gas do I need to keep from detonation?

thanks

 

[corvgreg]

Here's a location with that info:
http://www.kb-silvolite.com/page56.htm



[This message has been edited by corvgreg (edited 08-11-99).]

 

[David Nafarrete]

You can download Comp Cams Camquest software from their page for free. It has many utility programs that come in handy as well as a cam selection program. One of the programs calcs CR.

Dave

 

[Pat Kelley]

Save this page and use it offline.

http://www.jersey.net/~rforceno/crs/crs.htm .



------------------
Pat Kelley
66 & 67 El Caminos

 

[Randy Mosier]

Compression ratio is the total volume of a cylinder at bottom dead center compared to the volume at top dead center (including combustion chamber and head gasket thickness).

 

[Mojo]

Thanks guys...looks like I'm at about 9.7....I better start saving for that high octane...

mo.