Manley recommends .014 to .020.There has been a lot of concern about side clearence,mostly having too much.We have been told they correct way to measure the clearence is to measure the journal width and then measure the width of two rod caps then do the math.We still use the feeler guage check also,but find the aforementioned process more accurate.The clearence should be set to the manufactures specs.Different rods require different clearences,like aluminium that require more clearence.More is better than less the manufactures specs.