Yeah....did it that way in parking lot at Holidome in BG. Other rear fit fine in back seat area without backing plates and axles. 2.56 to 4.10 in 2 beers......
336/tire height X gear X MPH = RPM (no converter slip) So with stock tire height of 26.6" 336/26.6 X 3.23 X 70 = 2856 RPM. Add 150-200 RPM for converter slip, and you are around 3000 RPM 336/26.6 X 3.42 X 70 = 3024, so about 3200 RPM 336/26.6 X 3.55 X 70 = 3138, so about 3300 RPM With the P275/60R-15 rear tires, numbers are lower because they are 28" tall. 3.23 is about 2900 @ 70 MPH 3.42 is about 3000 @ 70 MPH 3.55 is about 3100 @ 70 MPH
The 3:23 I found is out of a 1970 442. It is a 12 bolt non post unit. It is stamped SE on the tube. As I am removing the 8.2 and putting the 12 bolt in will I need to have the driveshaft shortened ?
Might not be a true 12 bolt. Oldsmobile 8.4, 12 bolt cover, 10 bolts holding the ring gear. See the pictures in this link, round cover, u-bolt rear yoke, etc. http://jdrace.com/content/diff_id/12bABodyOlds.php https://v8buick.com/index.php?threads/12-bolt-1970.108431/#post-833994 https://classicoldsmobile.com/oldsjunction/oldsfaq/ofdif.htm SE is the Peg leg carrier with 3.23 ratio. SF was the Posi carrier. Not sure about the drive shaft length. Monzaz or BrianTrick would know for sure.
