Rear Axle ID Help - which car used a 12-Bolt posi w/ trailing arms (PIC) - Page 2 - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Transmission - Rearend
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #16 (permalink)  
Old 08-16-2005, 08:16 AM
djjc76's Avatar
Member
 
Last photo:
Join Date: Sep 2004
Location: Escondido, CA
Age: 38
Posts: 69
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Ok, here are some images I took...

Could it be from a '72 Chevelle? Did the car use trailing arms?






















    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #17 (permalink)  
Old 08-16-2005, 09:49 AM
djjc76's Avatar
Member
 
Last photo:
Join Date: Sep 2004
Location: Escondido, CA
Age: 38
Posts: 69
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
whoops

oh geez....it's a 10-bolt!
Reply With Quote Quick reply to this message
  #18 (permalink)  
Old 08-16-2005, 11:08 PM
Member
 
Last photo:
Join Date: May 2003
Location: Shreveport LA
Age: 64
Posts: 5,103
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Well it's definitely an 8.5" unit. The "15 41" is the tooth count on the gears (2.73 ratio), and the "72 12" is the manufacture date (Dec. '72) of the ring gear. I don't know what year they started using the S-shaped posi preload springs, but my '72 Nova unit has 4 coil springs, so I'd assume it's a '73-77.
Reply With Quote Quick reply to this message
  #19 (permalink)  
Old 08-17-2005, 04:56 PM
M&M CUSTOM's Avatar
Hotrodders.com Moderator
 
Last wiki edit: Transmission identification
Last journal entry: 1988 Suburban, the project continues.
Last photo:
Join Date: Mar 2003
Location: Northwest Pennsylvania.
Age: 43
Posts: 2,231
Wiki Edits: 9

Thanks: 0
Thanked 1 Time in 1 Post
Quote:
Originally Posted by djjc76
gear ratio is 2.73 (41 teeth on ring gear and 15 teeth on pinion). Both wheels turn together. There is a 15:41, 72, 8.75, etc stamped on the ring gear itself.


Assuming I use a 700R4, 350cui...would 2.73:1 be an ok choice to cruise on the highway? No burning rubber...
Everything you've posted show positively that it is a 1972 10-bolt axle.
I wouldn't recommend using the 2.73's behind a TH-700R4 unless you run some mighty small tires. This would be a great axle behind any transmission with a 1:1 high gear, the overdrive of .70 to 1 with 2.73's would give a final drive ratio of 1.91 to 1.

Going with 26 inch tires and an axle ratio of 3.73 and the TH-700R4 overdrive makes the final drive of my particular car 2.611 to 1
Reply With Quote Quick reply to this message
  #20 (permalink)  
Old 08-17-2005, 05:08 PM
djjc76's Avatar
Member
 
Last photo:
Join Date: Sep 2004
Location: Escondido, CA
Age: 38
Posts: 69
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
rear axle

Quote:
Originally Posted by M&M CUSTOM
Everything you've posted show positively that it is a 1972 10-bolt axle.
I wouldn't recommend using the 2.73's behind a TH-700R4 unless you run some mighty small tires. This would be a great axle behind any transmission with a 1:1 high gear, the overdrive of .70 to 1 with 2.73's would give a final drive ratio of 1.91 to 1.

Going with 26 inch tires and an axle ratio of 3.73 and the TH-700R4 overdrive makes the final drive of my particular car 2.611 to 1
yep, I am going with some small tires, 25.88" in outside diameter to be exact. I calculated somewhere online that with the current set-up, I can achieve 84 mph running 2100 rpm's...

Is there a difference between the '72 and '73 Chevelle rear ends?
Reply With Quote Quick reply to this message
  #21 (permalink)  
Old 08-18-2005, 04:22 PM
Member
 
Last photo:
Join Date: Nov 2004
Location: Indiana
Age: 60
Posts: 393
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
That should be great for highway cruising. Assuming normal size tires it should turn about 3000rpm at 70 with a 1:1 final trans ratio. With the 700r overdrive it will be less.
Reply With Quote Quick reply to this message
  #22 (permalink)  
Old 08-19-2005, 04:56 AM
Member
 
Last photo:
Join Date: Aug 2005
Location: Yackandandah.Australia.
Age: 53
Posts: 641
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
12 bolt

You don't show the back plate, if it has a serpentine ridge pressed across it, it's Chev. No ridge, it's Olds, but A body for sure. Top arms are triangulated, Impala's had paralell upper arms and a panhard rod. F bodies were leaf sprung prior to 82. 2.73 posi 12 bolt probably means 71/2 bb Monte Carlo or Chevelle. And yes, too tall for a350/t700, how heavy, what size tyre?
Reply With Quote Quick reply to this message
  #23 (permalink)  
Old 08-19-2005, 05:04 AM
Member
 
Last photo:
Join Date: Aug 2005
Location: Yackandandah.Australia.
Age: 53
Posts: 641
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
10/12 bolt

Just saw the new photo's. 73/78 corporate a body. Not rare, was it cheap?
Reply With Quote Quick reply to this message
  #24 (permalink)  
Old 08-19-2005, 08:32 AM
djjc76's Avatar
Member
 
Last photo:
Join Date: Sep 2004
Location: Escondido, CA
Age: 38
Posts: 69
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
rear end

The rear axle was free. I cant complain about that! It's a 10-bolt, 2.73:1 gears, positraction. The ring gear was made in December of 1972 so it makes me believe this is a 1973 Chevelle or Monte Carlo? Here is the back plate:



Reply With Quote Quick reply to this message

Recent Transmission - Rearend posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
New 12 bolt Rear/ questions. RObs71Nova Transmission - Rearend 1 12-27-2004 07:19 AM
What is This 12 Bolt Posi Out Of?? camaroman7d Transmission - Rearend 10 12-10-2004 04:57 PM
New 12 bolt rear? strikingthematch Transmission - Rearend 3 07-28-2004 11:41 PM
12 Bolt car and truck rear ends the same? zachscc Transmission - Rearend 2 01-18-2003 07:29 AM
12 bolt rear for a 1950 chevy truck solowookie Transmission - Rearend 3 11-17-2002 08:45 PM


All times are GMT -6. The time now is 08:23 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.