195KiB, 627x634, jkjjh.png View SameGoogleiqdbSauceNAO fortune Wed 29 Dec 14:39:34 2021 No.14028538 ViewReplyOriginalReport Quoted By: Hi /sci/ this is a p-v diagram of 4 stroke internal combustion engine. Can anyone tell me what dooes the diagram mean wtth the circled A ?