Guys running 12 bolts step in.
#1
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Guys running 12 bolts step in.
How many of you run the moser 12 bolt and how durable is it? I'm not planning on any 5000 rpm launches at the track anytime soon so I'm curious as to how much abuse it'll take on street driving with a few hard runs.
#4
if you are not even going to exceed 400 hp then I would just save your money and stay with the 10 bolt. As long as you are not hitting it hard you will be fine. My 10 bolt head fine with almost 500 rwhp, but I didn't 60' the car hard. I think the best 60' I ever had with the 10 bolt was in the low 1.8 range.
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Who or what led you to believe the 12 bolt is a ***** rear end? With 400 horse you won't even stress it, even with 5k clutch dumps. You should worry more about clutches and tires.
A 12 bolt Moser should last the life of the car. Although my personal preference is Strange.
A 12 bolt Moser should last the life of the car. Although my personal preference is Strange.
#6
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.
http://www.exoticperformanceplus.com....html?item=145
Now that the Moser nine inch can be ordered with the ABS option, I just don't see a reason to go with the 12 bolt. The prices are near identical to boot! Bob
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.
http://www.exoticperformanceplus.com....html?item=145
Now that the Moser nine inch can be ordered with the ABS option, I just don't see a reason to go with the 12 bolt. The prices are near identical to boot! Bob
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Damn that swayed me a bit harder to the 9". I like not having to pull fuses or stare at dummy lights. So about the backbrace option. What is that for>
Last edited by Blackhawk777; 05-15-2008 at 07:52 PM.
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#8
The backbrace is for those who are running well past 600 rwhp. It adds a support across the back of the housing to prevent flexing. Bob
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I have a friend that can get you the Strange 12 bolt or S60 rearend for a really good price. He owns a local shop where I live. If you are interested PM me and I'll get you the very low price on what ever you need..
#10
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I had a EARLY ver. of the Detroit Tru trac go in mine I bought it in 2004 (April) and it kinda sucked but I got a Eaton "updated" unit and its been fine.
12 bolts with eaton posi have lasted deep into the 9's but its a th400 car which autos are always easier then m6's
12 bolts with eaton posi have lasted deep into the 9's but its a th400 car which autos are always easier then m6's
#11
Who or what led you to believe the 12 bolt is a ***** rear end? With 400 horse you won't even stress it, even with 5k clutch dumps. You should worry more about clutches and tires.
A 12 bolt Moser should last the life of the car. Although my personal preference is Strange.
A 12 bolt Moser should last the life of the car. Although my personal preference is Strange.
Believe me, 5k to 6k clutch dumps **** things off. I was runnng a spec 5, with no clutch problems what so ever. I recently pulled the clutch out with 9k miles on it, only to find that it was in great shape.
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well I would have to say my own experiences with a moser 12 bolt. how do 2 broken posi units, then going to a spool only to start twisting 33 spline axles.
Believe me, 5k to 6k clutch dumps **** things off. I was runnng a spec 5, with no clutch problems what so ever. I recently pulled the clutch out with 9k miles on it, only to find that it was in great shape.
Believe me, 5k to 6k clutch dumps **** things off. I was runnng a spec 5, with no clutch problems what so ever. I recently pulled the clutch out with 9k miles on it, only to find that it was in great shape.
And I also agree a posi unit is going to fail in a hardcore racing application. There is a reason for a posi unit, street driving. If its going to be more hardcore racing then put a spool in it.
#15
http://www.exoticperformanceplus.com....html?item=145
This is the rear that I recommend. The nine inch and the 12 bolt are almost identical in price. Why settle for the weaker of the two? Bob
This is the rear that I recommend. The nine inch and the 12 bolt are almost identical in price. Why settle for the weaker of the two? Bob
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I'll probably go with the 9 since it is damn near identical in price and has all the options I want. (just noticed that they offer ABS now.)
#18
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Exotic Performance Plus has great customer service and some of the best quaility and I can truely say has done a great job with my 12 bolt. my ss puts 613 to the wheels, on occasion I run a 250 nitrous shot(progressive) true trac diff with 4.30 gears, complete bmr rear suspension, with a tex triple disc on my t56, over a year and no noise or problems comming from it, my exhaust is fiarly quiet, I can hear the rocks hit my inerfenders when I have the slicks on driving 5 mph, so there aren't any noises comming from the rear end.
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Still a hard decision. I'm not too concerned about the gear whine from a 12 bolt, seeing as how it's a street driven automatic car (No high rpm launches).
#20
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If it's an auto, keep the ten bolt until it pops. It might last quite awhile. Then consider upgrading to a 12 bolt. Autos with converters are pretty easy going on the rear end. The converter will give so the rear doesn't have to.