I have a question on the correct application for these SW speedometer adapters. Also were there at least two suppliers and two types - SW and AC?
.7333 dated N4 - 1969 April - possibly for COPOs with 14 inch tires and L78 with 4.10 gears?
.8241 dated N11 - 1969 November - possibly for 1970 Z28 with 4.10 and LS6 Chevelles?
I asked my dad about these and where they might have come from, but he is pretty old and could not remember exactly.
I think those are the two most valuable. I have 2 others with different ratios and dates shown in the pics, dated R - 1972 and V - 1976.
Well here are the part numbers and ratios from the 1972 parts catalog. Now I guess need to cross reference the part numbers.
Looks like the .7333 might be correct for 69 Chevelle with 4.10 including COPO but not Camaro?
The images below are for 1969.
https://www.yenko.net/forum/showthread.php?t=152702&page=2
Quote from: GMAD_Van Nuys on June 15, 2023, 11:49:56 AM
https://www.yenko.net/forum/showthread.php?t=152702&page=2
I have seen that. Nothing there directly answers my question.
The ones that have a part number starting with 6 are AC, part numbers starting with 3 are SW.
.7333 - the SW version is part number is 3932220
.8000 - the SW version part number is 3905497
.8241 - the SW version is part number 3950352
.8319 - the SW version part number is 3890575
.9743 - the SW version part number is 3950354
1.2020 - the SW version part number is 3950348
1.3000 - the SW version part number is 3950350
So those are the part numbers for future reference if anyone wants to look up the application.
Date codes are here via my buddy Jose. :)
https://www.yenko.net/forum/showthread.php?t=160435
I will see about adding the AC adapter information.
Maybe this can end up being in a report, or at least some of it folded into the transmission page.
Here are the ratios and part numbers for the AC adapters.
.777 - part number 6476736
.824 - part number 6476735
.8974 - part number 6273218
You can go here to see what the AC adapters look like.
https://www.yenko.net/forum/showpost.php?p=860798&postcount=6
Will go ahead and add the speedo gear chart since that may also come up in the future if this topic is searched.
70Z with 3.73 got the .8241 3950352
4.10 got the .7333 3932220
http://www.gmpartswiki.com/getpage?pageid=12662
Yes I believe that is correct for 1970.
I believe some 3.31 cars with TH400 also received the 3950352 in 1970 with TH400.
http://www.gmpartswiki.com/getpage?pageid=11446
1969 and possibly other years with 2.56 gears and 8.25 x 14 tires received adapter 3925673 with 1.1111 ratio. I will try to post a pic of one when I have a chance.
Quote from: bcmiller on June 17, 2023, 10:18:03 AM
Here are the ratios and part numbers for the AC adapters.
.777 - part number 6476736
.824 - part number 6476735
.8974 - part number 6273218
You can go here to see what the AC adapters look like.
https://www.yenko.net/forum/showpost.php?p=860798&postcount=6
Pic of one of the 0.824 AC adapters.