12 bolt needed?
12 bolt needed? I have 420 or more whp through an auto with a 3500 stall converter. I am looking to run 11's so I am guessing if I can get a hard launch I will eventually need a 12 bolt to hold up. my stock 10 bolt is still working perfectly has 3.23's and never failed to lock up with wheel spin. If I wanted to trade it and some cash for a used moser 12 bolt what kind of money will I have to put out?
did that but not enough to make the rear whine. now that I have front coilevers with drag springs i'm sure the 60's will get better. What I'm really wanting to know is how much i'm going to have to pay for a used 12 bolt on top of trading mine... Anyone know?
i paid 2600 out the door for a brand new 12 bolt from jaws gear & axel. stock 10 bolts are worth about 500. you may be lucky to pick one up for around 2000. best bet is buy a new one....
A Moser 9 inch is stronger than a 12 bolt, and the price is almost identical.
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.
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.
Link to my Moser 9 inch rears that are designed to bolt right into these cars. Prices start at $2,400.00 shipped with a Truetrac.
http://www.exoticperformanceplus.com....html?item=145 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.
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.
Link to my Moser 9 inch rears that are designed to bolt right into these cars. Prices start at $2,400.00 shipped with a Truetrac.
http://www.exoticperformanceplus.com....html?item=145 Bob
For an auto a 12 bolt will do fine. I'd go with a Strange unit. Used I see them go for $1,500-$1,800. Your used 10 bolt prolly ain't gonna fetch $500, $200 is more realistic. I sold mine for $100.
