I have a 1970 Cougar (351c w/FMX tranny) and a 1970 Cutlass (350 w/ TH350 tranny I think). Which one is easiest to add an overdrive transmission to and what does it take? Looking for most inexpensive path. I know new driveshaft or modify length but are there bolt ons for the back end of the tranny, was there an option in later years that don't require a computer, etc.
Thanks Bobby
You are asking a bit of a loaded question. The AOD with a small block bellhousing pattern is what you need for the
351c. This is the same patter as the 4.9L 6, the 302/5.0L and the 351W/5.8L engines. The AOD should be modified to accommodated the torque of the 351c and you will need a linkage to operate the TV cable of the trans. This regulates the line pressure of the AOD and can result in either hard /non shifts or light early shifts. In the case of the light shift, it may be a result of low line pressure with will result in a failed trans shortly. You will likely have to fabricate the linkage for you carb. Baumann Bros over in Anderson, SC may have a solution for that. A properly built/modified AODE or 4R70W with electronic controls would be better and maybe easier to setup without the fear of low line pressure because of a bad/poorly adjusted TV cable. The 4R70W is a better choice because it has better ratios to use with your 351c. Bauman Bros and others have electronic control setup available for you.You olds can be updated with a 700 series trans with the proper modifications. It also will require some electrical components to operate. These are also readily available. I believe you may be able to get tem for Summitt Racing or Jegs.
Hope this helps a bit Lugnut
This helps. Thanks for the response.
Bobby
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