which rear end?! 12 bolt or 9"

[muthstryker]

So im wanting to order my rear end and im stuck on what to get. Not quite sure, my car will be around 600-700 hp. Dont know weather to get a 12 bolt or a 9inch. Any suggestions would be awsome!

thanks

[ProdigyCustoms]

I am a big 12 bolt fan in GM cars. A 33 spline Tru Track 12 bolt or a 31 spline Tru Track will both handle your power.

My first choice is a 12 bolt. but with that said, I am putting a fab 9 in my personal car because that is what is available for the suspension I am running.

JMO.

[muthstryker]

hey frank, I was pming you a few months ago about this. You gave me a price for the whole rear end minus brakes. What does the rear end housing and axle only package cost? If you could PM me a price that would be awsome. I lost all my info and feel dumb for not saving it. That would be for a 12 bolt

[Memphis]

Heres a 12 bolt housing out of a 70 chevelle for $200, you can pick up some axles for fairly cheap from a number of places.
http://seattle.craigslist.org/oly/pts/1193607734.html
If that would need to be narrowed for you there is a guy up in Kent that does some pretty damn nice looking work for reasonable prices.

[team 68 chevelle]

whats the one we are using Frank?

[team 68 chevelle]

I am a big 12 bolt fan in GM cars. A 33 spline Tru Track 12 bolt or a 31 spline Tru Track will both handle your power.

My first choice is a 12 bolt. but with that said, I am putting a fab 9 in my personal car because that is what is available for the suspension I am running.

JMO.

Whats the one we are using?

[ProdigyCustoms]

12 bolt.

[Turbo67camaro]

I agree with Frank on the 12 bolt with a 33 or 31 spline Tru Track.

I went with a 12 bolt and 33 spline Tru Track differential.

I already had a 12 bolt, so I had Bill Scribner in Kent do the custom work on it to narrow it, build custom brackets for a G bar, straighten it, properly weld the tubes, etc.. His work is a true piece of art, and at very reasonable prices - http://www.scribnerwelding.com/home.html

In reality, it would probably be easier and cheaper to buy a Moser one fully complete from Frank.

Although, we have a member on this board who is an expert on rear ends, who is happy with many of Moser's parts, but not their labor when it comes to assembling one. I don't know if that is a legit concern, but perhaps the safest route would be to buy all the Moser parts, including the beefier housing, and get Bill to build it. He is a Moser dealer, and his work is off the hook.

[XLexusTech]

Nine inch all the way. Trac Nine it real nice
http://www.scandc.com/curriecraterearends.htm
Advantages: strength, No c clips which you will need eliminators at your HP, Bigger bearings, plenty of options and parts are easy to get. and the ability to change ratios in 1/2 hr.

Seach for posts by chicane and read everything he says twice :-)

[Rhino]

Nine inch all the way. Trac Nine it real nice
http://www.scandc.com/curriecraterearends.htm
Advantages: strength, No c clips which you will need eliminators at your HP, Bigger bearings, plenty of options and parts are easy to get. and the ability to change ratios in 1/2 hr.

Seach for posts by chicane and read everything he says twice :-)

I do completely agree that the 9" is a good rear, although I prefer to stick to a GM rear in a GM car. It's just a personal preference. You really can't go wrong with either.

Most of the issues you bring up with the 12 bolt are resolved by moving to a retained bearing setup. The 12 bolt I'm building is using a moser end with a big ford style bearing and a GM bolt pattern.
I'd like the ability to quickly change ratios, although it's a "want to have" not a "need to have." In all actuality it would happen very infrequently.

[Vegas69]

9" eats up a little power from my understanding. You can bake your cake and eat it to with a 12 bolt with big ford ends. I like mine. 15% drivetrain loss on torque and 16% horse with 33 splines and true trac.

[rickk]

9'' is the only way to go.
rick k:1st:

[big gear head]

I like the 12 bolt, especially the Moser 12 bolt. It's much stronger than the original 12 bolt. You can get the Eaton Posi for the 12 bolt, but not a 9 inch. If you want a clutch type limited slip differential the 9 inch is limited to a Traction Lock, which is weak, or the Auburn, which is JUNK.

[86Cutlass383SR]

I called Moser a few times concerning a 12 bolt housing and axle assembly for my g-body. They have housing ends which uses the axle retention like the Ford style (bolt in eliminating the GM c-clips) but have the GM bolt pattern so any standard GM 4 bolt brakes (like the planned LS1 rear disc in my case) will bolt right up. Best of both worlds.

[Vegas69]

Are you serious????

[86Cutlass383SR]

I'm fairly sure that's what they told me. They said it uses the Ford style bearing that presses on the axle and uses the retainer to hold the axle to the housing but the end is drilled for the GM 4 bolt brake pattern.

It's possible I misunderstood him but that was the general idea I was left with.

Straight from the Moser Housing End section, "The Chevrolet ends accept the large Ford style bearing, but still utilizes most Chevy drum and disc brake set-ups."

[ProdigyCustoms]

Nope, you are correct. We call that a Chevy special.

[Vegas69]

I'm fairly sure that's what they told me. They said it uses the Ford style bearing that presses on the axle and uses the retainer to hold the axle to the housing but the end is drilled for the GM 4 bolt brake pattern.

It's possible I misunderstood him but that was the general idea I was left with.

Straight from the Moser Housing End section, "The Chevrolet ends accept the large Ford style bearing, but still utilizes most Chevy drum and disc brake set-ups."

I was just messing with you... That is a 12 bolt with big ford ends.

[big gear head]

https://static1.pt-content.com/images/noimg.gif (http://rides.webshots.com/photo/2974101030041712107jPqQbL)
Here they are. This is a set that I installed on a Chevelle housing. The one in my hand is the original that I cut off of the housing and the new one is installed. They both have the same bolt pattern for the brakes, but the new one takes the large 9 inch Ford bearings. You need to know that the brakes need to be modified a little to work with the large bearings. If you use the stock drum brakes you must bore the hole in the center of the backing plate to 3.155 inches to fit over the bearing. If you use disc brakes then the caliper brackets must be counterbored about 1/8 inch to fit over the bearing. The caliper bracket in most cases will take the place of the retainer plate.

[86Cutlass383SR]

Todd...ya had me second-guessing myself! :pat: I'm keepin' my eye on ya now... LOL