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If the 340 was so great why did Mopar can it and continue building the 360 in the middle 70s...?



I'm not siding with the 340, but it's my understanding that it was discontinued in favor of the 360 for emissions reasons. Smaller bore produced less emissions with a more complete burn.

'73 340 vs '74 360 is the best comparison. Only bore & stroke is different & 360 wins. Only other variables would be state of tune and the rest of the car. 340's do like a little more gear, but I can't see that being a dominant factor.