I found out my coupe is an 8:1 compression ratio model, was this an option? wahy would someone order it this way? thanks

Submitted by david.kenny@sy… on Fri, 05/18/2007 - 22:15

If you look at the thermodynamic cycle on which a compression ignition engine is based i.e. the Otto cycle, you will find that power output per mass of air ingested is a direct monotonic function of compression ratio, although it is less than linear. Therefore, increasing compression ratio increases power for a given displacement. Also, the thermodynamic efficiency improves with increasing compression ratio, since, with the increased compression ratio, the heat rejected to atmosphere through the taipipe is a lower portion of the total heat released by combustion. This means that fuel consumption shuold be reduced with increased compression ratio.

Submitted by wcjssj@comcast.net on Thu, 03/08/2007 - 13:20

Compression ratio really isnt that important. If your head has ever been machined, you probably have a different compression ratio anyway. More important is how you engine does in a leak-down test. These cost around $100 and can be done by most mechanics. 1967 E-type S1 FHC