I ran into a guy today that claimed that the 9" weighs less than the 12-bolt. I thought it was the other way around. He said it is because the 9" is made out of lighter material or something. He also claimed that a 9" could be had for an f-body for $1200.

I don't believe any of this. Is it true?

 

Most 9" rears are heavier than most 12 bolt rears. Bottom line if you have an A4 car get a Strange 12 bolt. It's the lightest 12 bolt out there, and just as strong or stronger than the other 12 bolts. Plus it has a way better Torque arm mount design than Moser or KTRE.

If your building an M6 car, go for the 9" with all the best goodies money can buy.

I've had vast experience with M6 car and 12 bolt rears, and it's all bad.

 

Why is a 12-bolt bad for M6's?

Was that guy telling the truth about getting a 9" for $1200?

 

The 9" is certainly potentially much stronger. But I have lot's of 1.5 sec. 60' times with a 4,000lb car and an M6 and a 12-bolt. I would say that unless it's a track car designed to use something bigger than a 10" tire a 12-bolt is a good choice.

As far as weight, there are many different variations on the 9". Everything from a stock type setp to a fabbed aluminum sheet metal housing with lightweight internal parts. But in general terms, the 9" is heavier.

A new $1,200-1,300 bolt in 9" does not exist. Maybe he is talking about a housing without the center section or axles. That would be in the price range stated. Either will be >$2,000.

Rich