12 bolt 65 chev powerglide

[Michael Cohen]

does anyone know the ratio stock with 340 hp 409 and powerglide updating 12 rear end with limited slip differential original 12 bolt i purchased had a 273 ):

 

[Michael Cohen]

i don't know the ratio of the 10 bolt that came with the car my guess is 307

 

[Don Jacks]

More than likely 3.08,maybe 3.36 for the 409.2.73's didn't show up until 68-69 .The 3.07 8.2 ten bolt was quite common back then.

 

[Tim]

I had 3 powerglides 2 with 283 and one 327. All 3.08

 

[oldskydog]

Sure, I'll look it up since it's so hard.......https://www.gmheritagecenter.com/do...information-kits/Chevrolet/1965-Chevrolet.pdf

-All 327's got 12 bolts
-All wagons got 12 bolts
-All big blocks and likely fat blocks got 12 bolts
-Standard axle for a 325/396 which, Im sure was the same as the 340/409 (but only 396 shown in the Revised Feb, 65 AMA specs) was 3:07 with PG

 

[Tim]

Cecil, they may have changed the 327/12 bolt in 66. My 327 had a 8.2 (with 4 link) 10 bolt 3.08

 

[oldskydog]

That list was 65 specific. They did change up the gears in later years. You can look it up year by year to find out.

 

[Tim]

That list was 65 specific. They did change up the gears in later years. You can look it up year by year to find out.

ive noticed quite a few differences from 65 impalas to 66. Frames, suspension and stuff were the same but lots other things different. Seems like from year to year they changed stuff just because they could.