So how far up poodoo creek am I on this? I know I have stock 2.77 gears and 28 spline posi.... I know I need 31 spline carrier and new 2.77 gears to tolerate what I am going do with this... I have no idea about axle's and fitment and so forth so this is going to be a learning experience and hopefully not one with fire or melted metal.

So questions:
What carrier and gears do I need to get that will fit the stock 9 bolt Borg Warner axle? Who makes them where do I find them? 9bolt.com says they don't have 2.77! I want to keep the 2.77 and the Posi-traction

Will I need new axle rods as well? What am I missing to support more power?

I really don't want to buy a new axle but is that my best choice? I hope not!

I may have a 6.0 iron block alum heads LS with some turbos in my garage...And some new rods and pistons on order, Looking for a T56 getting stuff in motion slowly

 

I've never seen 31 spline axles for the 9 bolt. I've never seen a differential for the 9 bolt that will take 31 spline axles. I think you need a different rear end.

 

They exist!

 

Scrap the 9 bolt. I Had one years ago posi went out on me swapped it for a ls1 rear with a torsen diff. But for the power your looking to make you need to be looking at getting a moser 12 bolt or 9'' or like im doing custom built 8.8

 

Yes they do

This is the only option as far as I know

http://9bolt.com/carrierspares.html

 

As long as you don't hookup, you're not going to break it

 

Like doesn't Dana make something that will fit or something?
I really really don't want to swap axles

 

Huh? you said you need 31 spline axles, this is a diff that will take 31 spline axles, or you can get the cones and put them in your diff to accept 31 spline axles. You will have to get the axle shafts custom made though as far as I know, and I don't know what you would need to do about axle shaft bearings

 

31 spline axles would be a waste in this rear end. The small ring & pinion are still going to be the weak part and putting money into larger axles would not be worth it. Just get a 12 bolt from Moser, Strange or Mark Williams and you won't have to worry about breaking anything.

 

Greetings from Greensboro/Highpoint!

....here's a thread about swapping in a torsen differential. Those are more off the shelf than some other parts, but don't know that it's really a huge upgrade. Maybe a little. Weak point is still the physical size of the r and p. ....I'm with ObeyMyBird on this one. Ditch the 9 bolt. It's not really a performance rear, and ultimately you'll just chew it up.


https://www.thirdgen.org/forums/tran...installed.html

 

If you are going to stay with the 2.77 gears, you will never be able to change to a 2.92 or bigger gear set. 2.77 is a 2 series carrier, and you would need a 3 series carrier for more aggressive gears. The expense in converting the 9 bolt to a 31 spline with a 3 series carrier and 3.70 or larger gears would get you more than half way to a Moser or Strange rear where you can but replacement parts for them. The 9 bolt will never be as strong as a 12 bolt. In this HP game that we play, you either do it right the first time, or pay, pay, pay in the long run.

 

Yeah the more and more I read... The more I come to the conclusion I will need a new rear axle. I just gotta figure out how to get the stock length and match up all the brackets, I don't have the ability to do any welding so finding a used junkyard 9" and putting a new carrier and stuff is outta the question. I seen the custom Axel Hawks thirdgen has but it's like 2k... They don't seem to offer 2.77 or 2.73 either. In my experiences with hawks has always been you pay more $$$ because they just sell other peoples products at a bigger price. So I guess Moser and see what they can come up with for me.

 

I'm just curious as to why you want to stay with a highway power robbing gear like the 2.77?

 

I want a new hat that says "Bonneville 200mph" That and I am building the engine for top end torque, Trying to out do a Ferrari F40

 

You can get a moser housing and axle package for about a grand. Then you can try to find the proper 31 spline carrier and highway gear set out of a pick a part, or build a new center chunk anyway you want.

 

No welding required?

 

Yes sir, no welding