Cranking compression has a lot a variables, cam grind the main one, but not the only one. Performance trends engine analyzer will calculate what your cranking compression will be, give you an advance curve, and estimate spark knock for various octane fuels. Like every computer program garbage in garbage out, take the time to input accurate numbers and it is accurate within 10% used it for years. http://performancetrends.com/Engine-Analyzer.htm
