Yeah forget about 318 same stroke as a 340 and bore only marginally smaller then a 340. But because they originally had choke heads, low compression, single exhaust they are boat anchors garbage should be junked. They are not suitable starting points ect. And like I said, you can not reason with those ppl. They usually have no clue about building a performance engine, no amount of reasoning or rational thinking, 318s are junk, must be a 340 to be a performance engine.