The Mite
Part: 18
Moving the Miata Shifter on the Tranny

Stock Miata shifter The stock Miata shifter comes out at the end of the tranny, which corresponds to a shifter position in the car that is a bit too close to the driver for comfort.  If I could move it forward a bit, it'll be much more comfortable to drive and I won't have to but an "S" bend in the shifter like the old Cobras.
Stock Miata tranny tube There's four bolts that hold the shifter housing on the end of the transmission.  These have to be removed along with the two spring mechanisms that keep the shifter centered and the reverse lock-out mechanism that keeps you from going from 5th gear straight into reverse.
Cutting the miata shift rod Once the shifter housing and associated stuff is removed, the shift selector rod can be shortened.  The distance between the two sets of bolt holes holding the shifter housing is 103.5mm.  I will shorten the rod this amount, cut the front mounting bolts off of the shifter housing and use the rear holes in the housing and the front holes in the  tranny to mount the shifter.
Comparo of stock vs. shortened shift rods This is a stock shift selector rod on the bottom, and the shortened one on the top.  There's a hole in the end of the rod that a roll pin goes through to fix the shifter cup onto the rod.  This hole had to be re-drilled 103mm from the original end of the rod.  I had to take into account half of the 1.2mm hacksaw blade kerf and drill the hole 102.9mm from the end.  The hole is not exactly perpendicular to the shift selector at the end, so I had to make a jig that would allow me to drill the hole at exactly the correct angle through the rod.  Fun.
Gear selectors These are the gear actuators that the shift rod engages to select gears. 
Miata shift selector rods Here's the rod on the gear selectors.  As the shifter is moved left and right, the selector rod's "hockey stick" end moves into one of the three gear rods on the tranny.  Then, while engaged in one of these gear rods, you move the shifter forward or back and that pulls or pushes the rod in or out of the tranny to select gears 1-2 or 2-4 or 5-r.
Mess of tranny parts Here's the mess of parts that has to be re-assembled
Installing the rollpin on the miata shift cup The Shifter housing has been shortened, the tube that the shift rod goes through has been shortened and the cup that the shifter sits in is being reattached to the shortened rod via the roll pin seen sticking out.
Side view of the shortened miata shifter housing Here's a side view of the reattached housing, rod and tube.
the shortened miata shifter housing Top view of the housing  with no tube or shift rod
Comparison of the Stock Miata Transmission shifter location A comparo of the stock shifter rod tube on the top and my modified one on the bottom
Finished shortened miata shifter housing Re assembled and all 5 gears and reverse engage! 

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