12 bolt or 9"?

[ssms5411]

Which one would you get if you had the choice? I'm thinking 12 bolt because they are both pricing out about the same with a True Trac, and TA cover , and 33 spline axles.

[pace2006]

Re: 12 bolt or 9"?

If you were to have problems with snapping 10 bolts, I would look into a 12 bolt. Especially since you're running an auto, Steve. But I would avoid the Truetrac, if possible. They've been known to snap under those "sudden shock" situations that the Torsens are known for. Only difference is they are able to handle a little more torque than the stock units. You might be better off with a clutch-type Eaton in that situation.

[ssms5411]

Re: 12 bolt or 9"?

My fault , your correct it is a modified Eaton Posi with (800lb spring), I got them mixed up. My car def. hooks so I don't think a TrueTrac would be good then. Didn't know that about them. Thanks

[SilverRS96]

Re: 12 bolt or 9"?

9in all day. i love mine. a lot cheaper too since i built it. QP housing with moser 31 spline axles, detriot locker w/ 4.11s. Center section was a fresh rebuilt. in all it cost me 1700 shipped. show me a brand new 12 bolt that will b that cheap

[LETZRIDE]

Re: 12 bolt or 9"?

steve weren't you the one saying that you can use a 9" from an S10 or something on our cars, and you can pick them up for very cheap...all they need is a modification for the torque arm to work? I remember reading something about that and that you can get those for cheap....I thought it was pretty hard to break a 9" anyways?

[ssms5411]

Re: 12 bolt or 9"?

I think it was of a 95+ Ford Explorer have to have the TQ arm weled and LCA's welded on, I think that was it , it was a 8.5" rear, I'll probably end up with a 12 bolt , I'm just pricing them out right now, I'm just getting a list together and then will call a friend of my Dads who opened up a shop and see what he charges.

[LETZRIDE]

Re: 12 bolt or 9"?

PA racing has some shells you can look into as well, think they has some stuff listed for the 12 bolt for 500 or so...

[Choppers]

Re: 12 bolt or 9"?

I would look into a 9'. People over on ls1tech are breaking 12 bolts. Don't know how much power you are making though.

[ssms5411]

Re: 12 bolt or 9"?

Theres alot of performance shops around town I think I will see if the mechanic can find what he needs and I'll let him put it together and install it. Won't be for sometime , maybe end of the year. I just want to see how the turbo goes and see what #'s it puts down. If I can get 400 WRHP I will be very happy, but for summer I don't think I could run that much maybe 7 PSI with the meth, but in winter 12-15 PSI should be fine with the meth. Still have to see if the auto will hold the power, if not I can use my dyno #'s to find a converter and go with a built tranny. Either way a 12 bolt or 9" is a good investment esp. since I'm keeping the car forever.LOL

[cam98aro]

Re: 12 bolt or 9"?

steve weren't you the one saying that you can use a 9" from an S10 or something on our cars, and you can pick them up for very cheap...all they need is a modification for the torque arm to work? I remember reading something about that and that you can get those for cheap....I thought it was pretty hard to break a 9" anyways?

a 9" is a ford rear end, it would be pretty hard to find them off of s-10's since im sure there isnt many on them.

most drag racers running in the 8-9's use 9" rear ends, they are pretty tough, but i dont think a v6 camaro will make enough power to break a fully built 12 bolt unless it was abused.

[LETZRIDE]

Re: 12 bolt or 9"?

a 9" is a ford rear end, it would be pretty hard to find them off of s-10's since im sure there isnt many on them.

most drag racers running in the 8-9's use 9" rear ends, they are pretty tough, but i dont think a v6 camaro will make enough power to break a fully built 12 bolt unless it was abused.

I wasn't sure if it was a 9" for sure, but I remember reading something about the rear end off a truck was supposed to be the equivalent of the 9" or 12 bolt something like that, and it was less then half the cost to pick one up and all it needed was fabbing.

I would go with the lightest and cheapest one that will stand up to the job...if the 9" is cheaper and will more then stand up to 400 rwhp then why go with a 12 bolt and pay extra money if you never intend on putting down 700-800 rwhp? Put that extra money into something else.

[cam98aro]

Re: 12 bolt or 9"?

I wasn't sure if it was a 9" for sure, but I remember reading something about the rear end off a truck was supposed to be the equivalent of the 9" or 12 bolt something like that, and it was less then half the cost to pick one up and all it needed was fabbing.

I would go with the lightest and cheapest one that will stand up to the job...if the 9" is cheaper and will more then stand up to 400 rwhp then why go with a 12 bolt and pay extra money if you never intend on putting down 700-800 rwhp? Put that extra money into something else.

i was under the impression that the s-10's used the same rear end as we had.

the 10 bolt rears they put on the 4th gen fbodies are a hit or a miss, some people are using them putting down 450rwhp and beating the crap out of it and they hold up great, other peoples grandmas would be driving the car with 300hp and pull out from a stop sign and it breaks

me personally, i would just build whats already in there, im sure there are aftermarket differentials out there that are much stronger than what gm put in the factory, but thats just my opinion

[LETZRIDE]

Re: 12 bolt or 9"?

i was under the impression that the s-10's used the same rear end as we had.

the 10 bolt rears they put on the 4th gen fbodies are a hit or a miss, some people are using them putting down 450rwhp and beating the crap out of it and they hold up great, other peoples grandmas would be driving the car with 300hp and pull out from a stop sign and it breaks

me personally, i would just build whats already in there, im sure there are aftermarket differentials out there that are much stronger than what gm put in the factory, but thats just my opinion

Eaton :D....I bought mine when my torsen took a dump at the track...Eatons held up nicely, they say they are supposed to be "Bullet proof"...clutch style differential and the gears that it does have inside are forged...

[pace2006]

Re: 12 bolt or 9"?

I would look into a 9'. People over on ls1tech are breaking 12 bolts. Don't know how much power you are making though.

Most of the people on tech breaking 12 bolts are those with an T56 and short gears (4.10s) or are either A4/T56 putting down numbers over 600whp.

the 10 bolt rears they put on the 4th gen fbodies are a hit or a miss, some people are using them putting down 450rwhp and beating the crap out of it and they hold up great, other peoples grandmas would be driving the car with 300hp and pull out from a stop sign and it breaks.

That hit or miss effect is greatly influenced by how thick the gears in the differential are and what transmission is in front of it all. But I agree, chance can play a part in it.

me personally, i would just build whats already in there, im sure there are aftermarket differentials out there that are much stronger than what gm put in the factory, but thats just my opinion.

I also think Steve should take this route. Stick with what you have. See how those 3.73s and the turbo treat that Torsen. If it starts making noises or blows, start looking into a 12 bolt or Dana S60 rear.

Eaton :D....I bought mine when my torsen took a dump at the track...Eatons held up nicely, they say they are supposed to be "Bullet proof"...clutch style differential and the gears that it does have inside are forged...

Bullet proof til it meets 4.10s and a T56. :P

[LETZRIDE]

Re: 12 bolt or 9"?

Most of the people on tech breaking 12 bolts are those with an T56 and short gears (4.10s) or are either A4/T56 putting down numbers over 600whp.



That hit or miss effect is greatly influenced by how thick the gears in the differential are and what transmission is in front of it all. But I agree, chance can play a part in it.



I also think Steve should take this route. Stick with what you have. See how those 3.73s and the turbo treat that Torsen. If it starts making noises or blows, start looking into a 12 bolt or Dana S60 rear.



Bullet proof til it meets 4.10s and a T56. :P

That's why I don't play with sticks :D