Like this Phil? Not sure if the 20 tooth is correct for 3.42 This came out of 3.90, but who knows if that was even right.
Not sure how Buick followed suit,but Oldsmobile did NOT use the adapter for 3:42 gears,but they DID use them for 3:91 gears. All of my 4-speed Buicks had 3:64’s and had the adapter.
Brian, I was talking with another Olds friend yesterday he said his 342 geared 442 did not come with one. I have read were this was a reducer for 391 and 364 geared cars. Since my car is an AC car it is likely that I do not need this since my gearing is limited to AC. Thanks for your thoughts. I will still keep my ear out to see if anyone has any other varying thoughts.
You wouldn't happen to have one of the orig. Stewart-Warner adapters for 3.64, would you? As far as the OP's request, Buick didn't use the external type adapter/reducer for 3.42.
Yes,I have two of them,but not for sale. One is for my own car. They are one of the rarest parts to find for cars from this era.
Yup. Ford used the same SW part number but it looks to be configured a little differently & they're super expensive but do come up for sale.
The Speedo adapter was only used on Non AC Buick GS M21 muncie 4 speed cars with ON 3.64 or optional OZ 3.91 axles. Standard 1970 GS 455 4 speed 3.42 gears and GS AC Stage 1 M21 4 speed cars had no speedo adapter.