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Old 08-25-2003, 08:57 PM
  #236  
Joel Lagace
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The problem with EVO gears going is the way the centerline is built.

TC3/SD/PRO4:
-2 bearings front gear box
-1 bearing befor spur
-2 more bearings in rear gear box
-center shaft is "floating" within outdrives
Basically this design ensures the Drive gear at either end in captured securely within the gear boxes and that the shaft is floating.

EVO 3:
-1 bearing front gear box
-1 bearing before spur
-1 more bearing in rear gear box
-center shaft goes full length of car from drive gear to drive gear and is "keyed" into each gear.
This design provides an almost zero back lash or hesitation in the acceleration but the lack of bearing support allows movement of the drive gears during a hard hit or with mod motors(maybe). Basically the gear can move damaging the ring gear.


So if your car hits dead on to a wall with the tc3/sd/pro4 design there is some give in the center line due to the floating shaft. But with the evo3 that shaft has no where to go so there is the chance of flexing that will cuase drive gears mesh to move.

Cant prove this but all i know is that my SD is has gone through no ring gears nor has my 2 year old tc3. The 2 guys runing evo3s blow through one a race.
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