Guys also remember the total capable tooth count of the tc4, both lower(89t) and higher(102t) tooth count !!! If you're wondering what I am referring to, please understand that you can't make any size pinion fit with any size spur in the tc4 . If the total tooth count of the pinion added to the total tooth count of spur is less than 89 or greater than 102, then the (pinion/spur) combo will not mesh well ! 89< (pinion+spur)>102 !!!!!!! So a 55t spur will only mesh with pinions ranging from 34t up to 47t !!!!! etc.
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