Need help building a new rear end

[TnBlkC230WZ]

I blew my 12 rear at the last autocross. Essentially, It started vibrating and I kept driving (dumb), then the pinion nut came off causing the pinion gear to eat the posi carrier. The rear in this car is the only original part left and is long over due for a rebuild. As I see it I have four options and more options within those four. I need lots of help selecting the right rear for how I use the car.

The car is a 71 Nova that is mini tubbed. Still has 255/45R17 tires, but plan to install 295/35R19 on Corvette rims (I have the rims) It also has a CA Chassis Works G-Bar suspension. The car is a daily driver with lots of autocross and some road racing. (I'm working to get my competition license by this summer). It has an LS3 eRod engine and T56 magnum. My 3.73 gearing is pretty good, but may change to obtain 150 MPH in 5th gear at 5800 - 6000 RPM.

Recent upgrades to the current axle: New Moser axles, Willwood DynoLite Brakes with P-Brake, and aluminum Dif cover. I really want to reuse the Wilwood brakes

Some questions:
1. What type of posi unit should I use. I don't mind a little noise for the sake of reliability. I have $500 - $600 for the Posi?
2. Should I insist on non C-clip axles. I just bought the new Moser axles, but I can sell them?
3. Can the factory 12 bolt be built to hold up to the use it will see?
4. Will I need a new drive shaft if I get a Ford 9 inch or Dana 60 rear.
5. I was looking at the Strange axle ends with 12 bolt pattern and 3.150 openings. How do these work?

My Options:
1 Rebuild what I have. Given it is an original GM 12 bolt, I'm sure it has some value. I think I still have the old axles too.
2. Buy a new 12 bolt from Moser or Strange.
3. Get a 9inch from Strange with the correct brackets from the CA suspension
4. Get a Dana 60

Need help guys. there are sooo many options and I'm not an expert. I have a $2500 budget, but can increase if I sell the old parts

[ChevelleNV]

Go with the Strange S60.... I looked at building a bullet proof 12 bolt and couldn't build one for the price the S60 cost me.

[raustinss]

I'd buy the Moser axles and possibly the diff cover too if you aren't going to use [email protected]
Ryan

[TnBlkC230WZ]

Ido like the idea of a dana60. Are they as efficient as a 12 bolt or do they have the 3% power loss like a 9 inch

[ChevelleNV]

You will see some power loss since it is a much larger ring gear than the 9 inch or 12 bolt. I would strongly suggest you give the guys at Strange a call and they can give you some more accurate estimates on power loss. I myself chose it for the fact that it is a much bigger and tougher unit then the 9 inch or the 12 bolt.

[72'Monte]

rebuild that 12 bolt.get a true trac posi unit.and c clip eliminators for the axles.i just redid my 12 bolt.

[Motorcitydak]

I can never recommend a ford 9 inch enough. I have a Moser full floater axle for my car. Less the 3rd member and brakes, you can get one for around $1000. You want that different gear for your 5th gear, buy a 2nd 3rd member and you can have a eco gear and the track one. They can be changed out in about 30 min. With a full floater you can remove the 3rd with the tires still on the ground if your wheels have a decent size hub. You will never have to worry about breaking an axle shaft and losing a tire or the shaft eating the inside of your axle tube. No brake knock back either. They will weigh less that a 12b or 60 as well. Esp if you get the aluminum center section like I plan on doing. You should be able to use those brake calipers on this axle, you would just need to get rotors of the same thickness. You may have to make mounts for the caliper's tho. Sell off some of the other parts and you will meet that $2500 budget easily. Possibly even without having to sell that stuff. They come with a 5x4.75 bolt pattern as well

[TheJDMan]

I second the Moser 9" floater. There is no better setup for auto-x or road racing than a full floater. They say a 9" is something like 2 or 3% less effecient than a 12 bolt but lets be honest here, unless you are driving at 100% you will never know the difference and the ability to quickly change center sections more than compensates for any power loss. You can buy a new bare Moser 9" floater complete hubs, drive plates, bearings/seals and axles for $879

http://www.moserengineering.com/circle-track-packages-and-parts/moser-9-full-floater-9.html

68016

[72'Monte]

if you go with a 9'ford.check out http://www.quickperformance.com/.i got a lot of parts from them.good people.