Just out of curiosity: > http://drcwww.uvt.nl/~bogaard/heads.htm I assume that if you put a head from a larger engine on a smaller block, you could mill the head to bring up the compression, but how do you run a head with a displacement of 21.4 cc on a 1275? Wouldn't that give you nearly a 15/1 ratio? 318.75 divided by 21.4 =14.895