There's more to it than the 22 cu inch difference 318s have lousy heads...low compression etc. Sorry had to chime in saying the only difference is 22 cubes is a misstatement. When talking LA 318 vs 340 stock for stock.
You don't get it. Try reading and understand. 318, J heads (71-72 340/360 heads), cam, intake, and 4 barrel carb. It is just 22 cu in difference if you have all the good stuff. Actually if you have the same heads and same compression, it will have the same horsepower, just run a little higher rpm.
