'88-90 trans

• '88-90 trans
  Posted by Dezsled on 31 Jan, 2013 11:49
• Which gears are closer ratio in a '88-90 trans vs '87?
  
  3rd & 4th? 4th & 5th?
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• #1 Reply
  Posted by Heminutt on 31 Jan, 2013 11:51
• i think its 4th & 5th
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• #2 Reply
  Posted by Stpltn250r on 31 Jan, 2013 12:02
• 88 & up trans 4th & 5th.
  
  4th - 1.100:1
  
  5th - .909:1
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• #3 Reply
  Posted by Dezsled on 31 Jan, 2013 12:12
• Thanks.
  
  Now to see if the trans i scored is in good condition.
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• #4 Reply
  Posted by Stpltn250r on 31 Jan, 2013 13:32
• I think 87 is 4th - 1.045:1.   5th - .863:1
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• #5 Reply
  Posted by Glamisrider on 04 Feb, 2013 10:53
• The 88-90 trans has the closer ratio 4th & 5th than the 87.
  
  Now if you look at tooth count the 4th drive or driven has the same tooth count but if you mic it the diameter is different so you need both the drive & driven to swap the gears out.
  
  Another trick I learned from the fisherman is to only swap out 4th, making 3rd & 4th closer ratio but leave the 87 5th so it's taller and you can go faster on the top end.  this is how mine is and when I get in to 5th and the pipes lit it'll boogie
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• #6 Reply
  Posted by El Diablo on 04 Feb, 2013 11:18
• Quote from: Glamisrider on 04 Feb, 2013 10:53

  The 88-90 trans has the closer ratio 4th & 5th than the 87.
  
  Now if you look at tooth count the 4th drive or driven has the same tooth count but if you mic it the diameter is different so you need both the drive & driven to swap the gears out.
  
  Another trick I learned from the fisherman is to only swap out 4th, making 3rd & 4th closer ratio but leave the 87 5th so it's taller and you can go faster on the top end.  this is how mine is and when I get in to 5th and the pipes lit it'll boogie
  

  
  So those of us with the 88-90 trans can swap in the 5th gear drive & driven from an 87 to have the higher top speed?
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• #7 Reply
  Posted by Chuck D on 04 Feb, 2013 11:50
• Here it is straight from the service manual. 88 and up
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• #8 Reply
  Posted by Chuck D on 04 Feb, 2013 11:51
• 87 straight from the service manual
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