I have a 2000 Trans Am, A4 and mods are listed in my sig. I am pushing 430 hp at the wheels and I want to upgrade my rear end before it breaks. I plan on adding a 150 shot of nitrous in the future but the rear comes first. I am undecided if I should get a Moser 9" or 12 bolt. The car is mostly drag strip driven and is not a daily driver. Any suggestions on which one I should get and what type of center I should get. I would like to at least go with 4.10 gears. I would like everything to bolt right up just like a stock rear end. Any input will be greatful.

 

just letting you know you're probably going to want to brace yourself for everybody e-yelling at you to use the search button or that a 12 bolt will work great but a 9" will still be stronger and easier to work on...

 

Yea I figured that but I did do a search and people say different things. I got go with strange, go with Moser 9" and go with Moser 12 bolt.

 

haha yeah you'll have that alot on here. best bet is to talk to Bob at EPP or Scott at Driveline Solutions. they're great at helping people out and they'll probably be on this thread before too long anyways. i'm guessing they'll get you set up with a moser; full spool, 4.11s, and a nodular center...just a guess. (i'd personally get an ebay center though...got mine for 250 fully assembled with gears and bearings in great shape). i'm still trying to save a little cash back to buy a housing from one of them. good luck though.

 

Bob will get you a nice setup for a decent price. Either would be fine since you running an A4 however full drag ....9' might be suited to handle the abuse. In my experience the 4.11's are better with an M6....Bob can/will get you squared away on it.

 

Thanks guys, I appreciate it!

Here is the link to the Moser 9 inch, which currently on sale through the holidays.
http://www.exoticperformanceplus.com....html?item=145

Put a 12 bolt into a early Chevelle, Nova, Camaro, etc and you can beat the crap out of it, and not hurt anything. Put one into one of our cars with a torque arm, make a couple 4000 to 5000 dragstrip launches, and I can just about guarantee you'll pick up gear noise. If it is a drag only car, you'll never know or care about the gear noise. Drive your car home from the track, and the noise will drive you nuts. I feel the torque arm stresses the 12 bolt housing, causing distortion. We have never seen this happen with the 9 inch housing.

Exotic Performance Plus strongly recommends the Moser nine inch. This rear is even tougher than the Moser 12 bolt, and the horsepower of the late model F Body cars keeps escalating every year, which requires a very strong rear. With the recent introduction of the 6.2L GM aluminum block and the excellent flowing 6.2 litre heads, the horsepower of these cars is going to just keep climbing at a very fast pace.The nine inch will handle the power, plus we prefer the way the torque arm is bolted to the nine inch in the same way the oem rear-end is attached. (This is the only good thing about the stock 10 bolt...) The Moser 12 bolt uses four short bolts to attach the torque arm, and they have a habit of loosening up, even when loc-tite is used. Why the nine inch is stronger than the 12 bolt. The 9-inch has an internal rear-pinion support that also supports the gear end of the pinion to limit gear deflection under high torque loads. This seems to be the major reason why the 9 inch doesn't start whining after high rpm clutch dumps, when the 12 bolt will pick up noise.The 9-inch locates its pinion gear lower on the ring gear to improve tooth contact, than the 12 bolt does.The 9-inch has a 0.125-inch larger ring-gear diameter and internal pinion support than the 12 bolt does. This is not much of a difference, but it is worth noting. Bob

 

9 inch, it's simpler..

 

Honestly, if you do a search you will see that in the last year EPP has been in every thread woth the same copy and paste.

With that said, YOU have to tink about what your goals are and do YOUR research from there. How much track does it see? What do you launch at? Future plans?

A S60 could be had for cheaper and is damn near close to the 9.

As with any rear, you need to ask yourself if that is what you need. Is this a hobby atthis point in time? Or do you seeing youself having this car for a long time with lots of 1320 time?

 

He was asking whether he should go with a 12 bolt or a nine inch. I've had both in my Camaro, and we have sold more Moser rears than anyone else. The Dana 60 is the heaviest one, why go with it when the nine inch will handle an eight second car? Bob

 

Why does it look like the rear tires are off the ground in the above pic?

 

They are, we were invited to a wheelstand contest with Lou Santaigo that is going to be televised.





Here is Ted talking into the camera. Bob

 

Will the Moser 9" bolt right in without any mods? I have an adjustable UMI Torque Arm, will this bolt right on to a Moser 9"?

 

The Moser 9" is a good option. It will bolt up to your existing suspension parts. I would think about the 4.10 gear if you plan to spray. What size tire will you run?

 

Lou is the MAN.

 

i love my moser 12 bolt im making about 550whp made over 100 passes this year 5500rpm dumps cutting 1.4 - 1.6 60's. i dont think the gear whine is to bad, it dont bother me, and i put about 10k street miles on it this year. only complaint is that the top torque arm bolts do want to get loose on you and you must check them every so often.

 

I see this all the time. For obvious reasons variables are what decide which is better.

 

The way the 12-Bolt mounts the Torque Arm is pretty much what made me decide against it.

 

I have heard of people having problems getting the UMI torque arm to work with a Moser 9 inch. Bob

 

dude get a 12 bolt. At your power level you dont need a 9 inch and 12 bolts eat up less power.

 

I have 26" tall tires. What gear should I run if I am spraying?