1994 5.0L removed the T -5 and installed a Tremec 3550 The speedometer is now wrong.Reading 62mph but actual speed is 70mph How do I find out what speedo gear to buy?The gear in it now is black?>(T-5 gear ratios 1st 2.95,2nd 1.94,3rd 1.34,4th 1.00,5th 0.63)............................................. ............................(Tremec 3550 1st 3.27,2nd 1.98,3rd 1.34,4th 1.00,5th 0.68 tires 245/45/17 Diff.ratio 3.08)............................................. ..........Hanlonmotorsports.com Speedo calibration says to use a 7 T .412 is this correct?
http://www.hanlonmotorsports.com