Gear Vendors OD on a 73’ Javelin

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   Th GV unit is a HD version of the Laycock-DeNormanville unit AMC used in the mid 70s for 2-3 years. In fact, GV got it's start by buying leftover AMC units when AMC stopped using them, then getting a license to build a heavier unit. 

While it's possible to shift eight forward speeds, it's not practical. 1+OD is very close to 2nd, and 2+OD is very close to 3rd. So close as to be impractical to shift that way. Might be handy on a big motor home pulling up mountains, but not on a level even for something like that (unless really loaded to the max!).  That's why the AMC Twin-Stick trans is unique -- has a big gap between 2nd and 3rd gears if you shift without using OD on 2nd. They didn't use OD with 1st at all. 

The only drawback to the GV unit is you have to tear your fresh 727 apart to change the output shaft. That will incur some added expense.  You might save a little over adapting a GM 2004R/700R4, but not that much. Still, the GV unit is a good choice, it's mostly a matter of preference at this point. 

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farna Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Moderator Lost Dealership Project Joined: Jul/08/2007 Location: South Carolina Status: Offline Points: 19689	Post Options Post Reply Quote farna Report Post Thanks(0) Quote Reply Posted: Jan/18/2021 at 6:36am
	Th GV unit is a HD version of the Laycock-DeNormanville unit AMC used in the mid 70s for 2-3 years. In fact, GV got it's start by buying leftover AMC units when AMC stopped using them, then getting a license to build a heavier unit. While it's possible to shift eight forward speeds, it's not practical. 1+OD is very close to 2nd, and 2+OD is very close to 3rd. So close as to be impractical to shift that way. Might be handy on a big motor home pulling up mountains, but not on a level even for something like that (unless really loaded to the max!). That's why the AMC Twin-Stick trans is unique -- has a big gap between 2nd and 3rd gears if you shift without using OD on 2nd. They didn't use OD with 1st at all. The only drawback to the GV unit is you have to tear your fresh 727 apart to change the output shaft. That will incur some added expense. You might save a little over adapting a GM 2004R/700R4, but not that much. Still, the GV unit is a good choice, it's mostly a matter of preference at this point.
	Frank Swygert