is there a table somewhere that shows detonation degree threashold per cr(compression ratio) and ambient intake temp per fuel grade at given load points? TIA

 

Its actually not that simple since there is no "standard" since there are too many variables which can make a specific combination more efficient than others. Many people talk about 12.5:1 compression ratio and its vulnerability to ping when using pump gas, etc.... honestly thats jsut a myth because, there is a lot more going on when the cams are degreed and the motor is tuned via camgears. The overlap actually reduces the cylinder pressure that everyone is so scared of. Second, the valve deshrouding, quench shape, deburring material inside chambers, exhaust combination, etc. all play such a big role that its not a simple answer.

Greg

 

oh ok, well my cr is not that high (8.8:1) and have advanced it considerably, i just wanted to do some reaserch before i advance some more

 

Go with your good ear or a J&S Safeguard...