13:1 Compression Pistons in 340 Small Block
Sometimes it’s better to just NOT use what you have laying around...
Roger that..... mild street build, pump fuel, and 12:1 or 13:1 static CR don't go together. You are right OP, these pistons would typically be usable only with certain large cams and fuels.
If you use them with too small of a cam on pump fuel, then the engine will experience what is called detonation, which will destroy things in short order... unless you use the different fuels being suggested. If you put in a big cam to prevent that, then low RPM performance, and what is termed driveability, goes into the toilet.
Help us all (and yourself) by explaining better what you want to do with this engine/car. 'big block buster' is a bit ambiguous, and you can do that with a highly modified /6 and a lightweight early A body! Do you want to run pump fuel? Is economy important to you? Drag race only? Or are good street drivability and good cruising manners the most important things? Auto trans or manual? Picking parts all starts with the application....
And welcome to the site! This is pretty knowledgeable group.
