12 bolt for C-2
Thread Starter
Intermediate
Joined: Jun 2013
Posts: 39
Likes: 5
From: Southern Oregon
12 bolt for C-2
Does anyone make an out of the box fully prepped 12 bolt, ready to install conversion for a C-2 or even a 10 bolt with 12 bolt internals? Not interested in a kit that has to be machined, too much brain damage.
Burning Brakes
Joined: Nov 2011
Posts: 1,170
Likes: 201
From: Willoughby Ohio
If you go 12 bolt the only gear ratios available are 3:73, 4;11 and 4:56. For the guys making big power the extra machine work is worth it
because the 12 bolt differential case is 4x's stronger than the 10 bolt.
because the 12 bolt differential case is 4x's stronger than the 10 bolt.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
12 bolts are strong but not bulletproof, If I had to convert Id be calling Moser and asking them to do a 9 inch or Dana. Plus gear swaps are easy
Even a well built 8.8 can take quite a bit,just food for thought
Even a well built 8.8 can take quite a bit,just food for thought
Last edited by cv67; Mar 30, 2019 at 03:03 PM.
Tech Contributor
Joined: Aug 1999
Posts: 15,175
Likes: 3,983
From: Connecticut, USA
No, there is not an out of the box 12 bolt vette iron differential, they have to be built and yes that requires machine fitment. This conversion has been Tom Watt's of Tom's Differentials for 45 years. Tom passed away last year but stopped building them 10+ years ago. You would have to call Tom's wife, Jo Watt, to check on the availability of the parts. The center section is the same, there are two choices for axles- 1350 or 1480 depending on your power, trans, traction and driving potential.
So my question for you - what is your intended use, do you need a 12 bolt? 9" conversions are out there in both solid and IRS($$$$) These might be more of a package deal that you are looking for.
The quality of some of the parts today is not the same as it once was, the spiders Tom used and sold for years has changed. You can find them but they are expensive but are better then the current spiders. I stocked up on them when they were obsoleted about 8 -9 years ago. The 12 bolt spiders have a larger diameter cross shaft which uses a larger ID pinion gear set, the side gears are 30 spline.
The bearings are the same for both 10 & 12 bolts.
A real super-10 bolt uses 12 bolt parts and some other parts to beef it up. This is also a build to application deal.
Many times a correctly blueprinted diff with some mods would be all you need and one that you might be able to build at home depending your capabilities and tools.
