Home › Forum › Ask A Member › 1955 Mark 55 › Re: 1955 Mark 55
December 8, 2017 at 2:47 am
#68391
24-1 before the 50-1 oils came out. after that Mercury recommended the 50-1 I like to add a little more about 40-1 works fine for me. been using that since 1964.on there race motors only double the mix.