i have a 02 silverado half ton with a 5.3 i was wondering what the compression ratio is? the engine is bone stock. also, what is the highest compression i can have with 93 octane gasoline without having to worry about detentation? if these questions have already been answered i do apologize i was up all night last night searching. any info would be great thanks.

 

LM7 is 9.5 to 1 CR and I think you could go 11:1 on pump gas, without knock