9" or 12 Bolt on my Project?
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From: Baytown, TX
9" or 12 Bolt on my Project? Hey guys, I need some your help to make the right decision whether 9" or 10 bolt for my 1999 Trans Am's project. In about 2 or 3 months I am going to start working on my T/A, I am really excited to get this thing done, of course, I am not going to do this whole thing on my own lol. Soo more than anything my T/A should be pushing above 800RWHP easily when its completed. The engine is a 427 Stroker with a single 88mm PT, I will be using Water/Meth, the car will be a 4l80e automatic, etc etc too many things to list.
I have been researching about Moser's 9" and their 12 Bolt complete rear ends and it seems to me like more people tend to use the 9" differentials for manual vehicles, and 12 bolts for automatics. Why is that? Im thinking because manual vehicles are more aggresive because of the shifting? I have also read that 9" are used for more drag racing vehicles and 12 bolts tend to be the ideal differential for cars that will get more time in the street and wont see too much time at the track, but that also 12 bolts are good for the track.
My car will hit the street more than the track, I dont really plan on slapping some slicks on my T/A often, maybe once or twice a month, shoot, who knows, maybe with all that adrenaline it might get to be a habit
lol
What do you guys recommend for me?
Also one more question, idk if I can ask this question here but:
I plan on upgrading to C5 Corvette caliper brakes but will I able to use this brakes? or can I upgrade with some Wilwood brakes that Moser offers with their whole assembly?
Ive read that Wilwood brakes arent recommended for street use but my car wont get driven much, only cruise on weekends really.
Thanks guys, Alex!
I have been researching about Moser's 9" and their 12 Bolt complete rear ends and it seems to me like more people tend to use the 9" differentials for manual vehicles, and 12 bolts for automatics. Why is that? Im thinking because manual vehicles are more aggresive because of the shifting? I have also read that 9" are used for more drag racing vehicles and 12 bolts tend to be the ideal differential for cars that will get more time in the street and wont see too much time at the track, but that also 12 bolts are good for the track.
My car will hit the street more than the track, I dont really plan on slapping some slicks on my T/A often, maybe once or twice a month, shoot, who knows, maybe with all that adrenaline it might get to be a habit
lolWhat do you guys recommend for me?
Also one more question, idk if I can ask this question here but:
I plan on upgrading to C5 Corvette caliper brakes but will I able to use this brakes? or can I upgrade with some Wilwood brakes that Moser offers with their whole assembly?
Ive read that Wilwood brakes arent recommended for street use but my car wont get driven much, only cruise on weekends really.
Thanks guys, Alex!
Can't go wrong with a MWC fab 9 inch I would recommend first and be happy you did so in the end. Second choice would be the strange s60. It's a hoss and you pay in the weight it adds. But it's not going to break and also has good differential options
Thread Starter
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From: Baytown, TX
soo in case I was to go bigger on my HP I should just plan on upgrading to a 9"? Apart from being a great drag racing rear end does it affect street drivability in a bad way?Thanks for the tips!
Thanks for the tip! Do you know the torque capacity or RWHP capacity for the S60? Just like I mentioned on my last quote post the thing is that my plans could change in the future and might go bigger but of course that wont be any time soon lol
Streetabilty is fine with a 9 inch bolts up just like factory and can use all the aftermarket suspension components. MWC even has a watts link system if you prefer something like that.
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From: Baytown, TX
Nice! Im concerned about street drivability for the most part. Will MWC 9" rear end be able to use C5 corvetter brake rotors and pads? If not what other brakes can be used? I heard Wilwood brakes tend to wear down when it comes to street driving and braking.
MWC 9" and never look back. I just made a big post in his thread the other day. I did the S60 and had problems and it was SOOOO heavy....
The brakes should work fine if they are working on your 10 bolt now? Uses you same backing plates.
Mine has a spool and drives just fine on the street. Also have a 80 and the combo works great together. When you buy his rear, it comes with a very nice torque arm. If you get the S60 you will still need to get a nice Torque arm. He offers a nice anti roll bar upgrade also for cheap.
a 12 bolt is my least fav rearend. do a search, seems like a lot of people still break them.
Do it once and do it right and call it a day.
The brakes should work fine if they are working on your 10 bolt now? Uses you same backing plates.
Mine has a spool and drives just fine on the street. Also have a 80 and the combo works great together. When you buy his rear, it comes with a very nice torque arm. If you get the S60 you will still need to get a nice Torque arm. He offers a nice anti roll bar upgrade also for cheap.
a 12 bolt is my least fav rearend. do a search, seems like a lot of people still break them.
Do it once and do it right and call it a day.
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From: Baytown, TX
MWC 9" and never look back. I just made a big post in his thread the other day. I did the S60 and had problems and it was SOOOO heavy....
The brakes should work fine if they are working on your 10 bolt now? Uses you same backing plates.
Mine has a spool and drives just fine on the street. Also have a 80 and the combo works great together. When you buy his rear, it comes with a very nice torque arm. If you get the S60 you will still need to get a nice Torque arm. He offers a nice anti roll bar upgrade also for cheap.
a 12 bolt is my least fav rearend. do a search, seems like a lot of people still break them.
Do it once and do it right and call it a day.
The brakes should work fine if they are working on your 10 bolt now? Uses you same backing plates.
Mine has a spool and drives just fine on the street. Also have a 80 and the combo works great together. When you buy his rear, it comes with a very nice torque arm. If you get the S60 you will still need to get a nice Torque arm. He offers a nice anti roll bar upgrade also for cheap.
a 12 bolt is my least fav rearend. do a search, seems like a lot of people still break them.
Do it once and do it right and call it a day.
Thanks alot for the info, now I know which way to go 
Thread Starter
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From: Baytown, TX
https://ls1tech.com/forums/suspensio...brake-faq.html
And as fars as 17 inch wheels fitting you shouldnt have any problems, but I would do some research on the brake and suspension forum and wheels and tire forums to make sure
Hey guys, I need some your help to make the right decision whether 9" or 10 bolt for my 1999 Trans Am's project. In about 2 or 3 months I am going to start working on my T/A, I am really excited to get this thing done, of course, I am not going to do this whole thing on my own lol. Soo more than anything my T/A should be pushing above 800RWHP easily when its completed. The engine is a 427 Stroker with a single 88mm PT, I will be using Water/Meth, the car will be a 4l80e automatic, etc etc too many things to list.
I have been researching about Moser's 9" and their 12 Bolt complete rear ends and it seems to me like more people tend to use the 9" differentials for manual vehicles, and 12 bolts for automatics. Why is that? Im thinking because manual vehicles are more aggresive because of the shifting? I have also read that 9" are used for more drag racing vehicles and 12 bolts tend to be the ideal differential for cars that will get more time in the street and wont see too much time at the track, but that also 12 bolts are good for the track.
My car will hit the street more than the track, I dont really plan on slapping some slicks on my T/A often, maybe once or twice a month, shoot, who knows, maybe with all that adrenaline it might get to be a habit lol
What do you guys recommend for me?
Also one more question, idk if I can ask this question here but:
I plan on upgrading to C5 Corvette caliper brakes but will I able to use this brakes? or can I upgrade with some Wilwood brakes that Moser offers with their whole assembly?
Ive read that Wilwood brakes arent recommended for street use but my car wont get driven much, only cruise on weekends really.
Thanks guys, Alex!
I have been researching about Moser's 9" and their 12 Bolt complete rear ends and it seems to me like more people tend to use the 9" differentials for manual vehicles, and 12 bolts for automatics. Why is that? Im thinking because manual vehicles are more aggresive because of the shifting? I have also read that 9" are used for more drag racing vehicles and 12 bolts tend to be the ideal differential for cars that will get more time in the street and wont see too much time at the track, but that also 12 bolts are good for the track.
My car will hit the street more than the track, I dont really plan on slapping some slicks on my T/A often, maybe once or twice a month, shoot, who knows, maybe with all that adrenaline it might get to be a habit
lolWhat do you guys recommend for me?
Also one more question, idk if I can ask this question here but:
I plan on upgrading to C5 Corvette caliper brakes but will I able to use this brakes? or can I upgrade with some Wilwood brakes that Moser offers with their whole assembly?
Ive read that Wilwood brakes arent recommended for street use but my car wont get driven much, only cruise on weekends really.
Thanks guys, Alex!
Like my customers have already stated here... Do it once and do it right. The rearend and suspension for your car will be the second biggest investment for the car and the worst thing you can do is spend money twice. I can not tell you how many of the rearend and suspension customers I have already had aftermarket parts on their car and say " I wish I would have".
Do your searches and quotes and you will find that MWC has the best deals on any rearend or suspension component for your car, as well as the street and track experience to back it all up. The quickest and fastest stock suspension f-body cars on drag radials all run MWC rearends and suspension components. Even when you purchase street type fabricated 9" package from us you get the same housing, torque arm, and suspension component pieces that all the race winners get.
Feel free to give me a call and go over all the options for you. I can do custom brake packages, and even a complete assembled rearend that is ready to bolt in the car. Whatever your budget and needs are I am sure we can get you taken care of, no matter what rearend you decide on.
Thread Starter
TECH Senior Member
iTrader: (8)
Joined: Sep 2012
Posts: 6,963
Likes: 4
From: Baytown, TX
Like my customers have already stated here... Do it once and do it right. The rearend and suspension for your car will be the second biggest investment for the car and the worst thing you can do is spend money twice. I can not tell you how many of the rearend and suspension customers I have already had aftermarket parts on their car and say " I wish I would have".
Do your searches and quotes and you will find that MWC has the best deals on any rearend or suspension component for your car, as well as the street and track experience to back it all up. The quickest and fastest stock suspension f-body cars on drag radials all run MWC rearends and suspension components. Even when you purchase street type fabricated 9" package from us you get the same housing, torque arm, and suspension component pieces that all the race winners get.
Feel free to give me a call and go over all the options for you. I can do custom brake packages, and even a complete assembled rearend that is ready to bolt in the car. Whatever your budget and needs are I am sure we can get you taken care of, no matter what rearend you decide on.
Do your searches and quotes and you will find that MWC has the best deals on any rearend or suspension component for your car, as well as the street and track experience to back it all up. The quickest and fastest stock suspension f-body cars on drag radials all run MWC rearends and suspension components. Even when you purchase street type fabricated 9" package from us you get the same housing, torque arm, and suspension component pieces that all the race winners get.
Feel free to give me a call and go over all the options for you. I can do custom brake packages, and even a complete assembled rearend that is ready to bolt in the car. Whatever your budget and needs are I am sure we can get you taken care of, no matter what rearend you decide on.
