I've a BF and stock ZF6 speed, had anyone tried to put higher diff ratio for better acceleration for this ZF? Which workshop in Melbourne would do this stuff - tried and proven reliable by anyone of you guy? I would prefer some ratio between 2.9~ to 3.1 ( I dont know the exact numbers) however, fuel wise is still my 1st priority I just want a better acceleration than stock diff ratio. and if with new diff, who can recalibrate the speedo? my tuner or ford service? is it hassle-free to fix up the speedo with the new diff ratio? Cheers
