Can you guys list where you got your 12-bolts, and what brands they are. and how much you paid. I am looking for a 12-bolt but want to make sure I get the RIGHT one. There are so many manufactureres out there right now. thanks

 

Im interested in this as well, I see them on ebay going for 750 or so on average, but im not sure if they fit in my f-body.

 

if i got one it would most likely be from here.

http://www.spohn.net/product.cfm?productid=1336

 

Ack, man that is a bit pricey...

 

I'll be in the same shape you're in now. I have a '83Z very soon to have a 406, but I upgraded my T-5 instead of a T-56.....but I too have a 10 bolt.

I plan to find a used 10 bolt posi and swap the 3.73 ring and pinion I have in my one legger now, and hope it holds. I just won't have the $$$ for a 12 bolt for awhile....

A Ford 9" is an option too.

 

Actually, that is not a horrible price for the rear end. I just checked the local speed shop, and they wanted $2,055 for the Moser 12 bolt rear before the options.

They also told me something I did not know. 12 bolts are more efficient than the 9", thus making more rear wheel hp. Something about the way the gears align.

 

it has to do with the relation of the pinion to the ring gear. A 9 inch is very inefficient, I can tell you from experience they are very heavy too unless you get an aluminium housing.

 

Yeah, but all the stuff about weight and pinion placement doesn't mean jack in the real world. I read an article not too long ago where they ran a 9", a 12-bolt, and a Dana 60 in the exact same car, with the same gearing and style centersection in all the rears. There was no noticeable difference in strip times. A hundreth of a second or so, but if you looked at all the runs the difference between runs with the same rear were often speratated by a hundreth or two, meaning that the rears had basically no effect on performance.

In theory a 12-bolt has the least amount of friction because of the pinion placement. A Dana 60 is definately heavier than either a 9" or a 12-bolt (they don't call it a flying anvil for nothing).

The cheapest I've seen bolt-in 12-bolts for 3rd gens is about $1,650 directly from Moser. 9" Fords seem to actually be a little bit more expensive.

 

you need to consider shipping cost. also it's usually cheaper to buy the parts and do the assembly yourself.

 

Also, even if you buy a the complete kit from moser, you need to set it up anyways. My buddy has a moser 9" in his Z28, and the instructions pretty much said that the rear end needs to be re-setup.