12 bolt or 9in for Autox?
#1
12 bolt or 9in for Autox?
I know after my engine mods and 4.10s my 10 bolt is going to blow.
However, I am gearing my car towards more of a handler than a drag car. I plan on going full Koni/strano/UMI suspension.
Well I hear that people that put 9 inch rears or 12 bolts have handling issues (which makes sense since there is a mass change and the oem suspension design is not meant for it.)
So my question is, can I get an aftermarket rear end for handling or should I just roll the dice and keep the 10 bolt and replace it as needed?
However, I am gearing my car towards more of a handler than a drag car. I plan on going full Koni/strano/UMI suspension.
Well I hear that people that put 9 inch rears or 12 bolts have handling issues (which makes sense since there is a mass change and the oem suspension design is not meant for it.)
So my question is, can I get an aftermarket rear end for handling or should I just roll the dice and keep the 10 bolt and replace it as needed?
#3
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The 9 inch, if you are careful (and have deep pockets), should be able to be made lighter than a 12-bolt, and there are more differentials to choose from with a 9" type of center section. My vote goes to that if that is your primary concern...I went with a 12-bolt for fit and finish reasons.
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im in the same boat. im thinking of upgrading my rear in the future. i autox mostly, but once in a while hit the strip, or do a burnout here and there. i was debating whether or not to build the 10 bolt - weld axle tubes, TA girdle, torsen diff, etc - or to go with a new rear and not worry about it. from what ive been told, the torsen is only available for the 9in, not the 12. so id lean towards the 9in.
#6
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Street tires and autoX only - gamble on the 10 bolt. Throw a TA cover and stud kit on it, fill it with RP, and call it good. If you stay off the drag radials and hard launches, you have a decent chance it will last. Do up your suspension to totally eliminate axle hop and you should be OK.
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Viper, what gears are you running, and did you upgrade anything else in the rear end like the axles, cover, etc? I really want a T2R and I'm putting around 380 ft lbs of torque to the ground.
#11
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What is it about the upgraded rear ends that causes a problem? I have just started to get into road racing and haver turned many laps with my Moser 12 bolt + 4.10s. Back end feels firmly planted on the ground... in fact, before reading this post I had speculated that it might be to my advantage given the extra weight would help the over balance, if but by just a hair. I should add too, that the track I'm running at is very very smooth, no bumps to get things moving around.
But I'm admittedly ignorant here... so what about it is going to hurt me?
But I'm admittedly ignorant here... so what about it is going to hurt me?
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The T2R isn't available in many rear ends. Just the 10 bolt rear ends and the Ford 8.8 inch. I've heard good stuff about the T2R to put it simply and want to give it a try myself. I know there are various Auburn and Detroit TruTrac diffs available for the 9 inch, less for the 12 bolt.
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I would get a fabed housing 9in. I would guess this is 40lbs heaver than a 10 bolt. I would get a truetrack. It is gear driven posi. I got mine for 3200.00 with a torque arm. I sold my old torque arm and my cover 540.00. So 2700 for a 9in is not bad. I think the 40 lbs is a small price to pay. Also if you brake a axle the wheel will stay on the car.
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You're fine with a 10 bolt. The problem with the 10 bolts is that it doesn't hold well against shock loads, like launching with a 6-speed. Autocross is less violent on the rear end in that manner, I think you'll be fine.
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I also run an event that involves launching on not the best of surfaces with Nitto 555r drag radials (probably the best tire for the 100 treadwear restriction). I typically slip around ~3000 rpm.
In this event, having higher gear ratios helps. I think a 3.73 would help me, but I'm not sure how many people are running a 3.73 with a T2R. I think 4.10s would make me borderline shifting to 3rd which I don't want to do.
I'll probably just keep my stock end for the time being. I've had decent success with it so far.
In this event, having higher gear ratios helps. I think a 3.73 would help me, but I'm not sure how many people are running a 3.73 with a T2R. I think 4.10s would make me borderline shifting to 3rd which I don't want to do.
I'll probably just keep my stock end for the time being. I've had decent success with it so far.
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I would get a fabed housing 9in. I would guess this is 40lbs heaver than a 10 bolt. I would get a truetrack. It is gear driven posi. I got mine for 3200.00 with a torque arm. I sold my old torque arm and my cover 540.00. So 2700 for a 9in is not bad. I think the 40 lbs is a small price to pay. Also if you brake a axle the wheel will stay on the car.
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I also run an event that involves launching on not the best of surfaces with Nitto 555r drag radials (probably the best tire for the 100 treadwear restriction). I typically slip around ~3000 rpm.
In this event, having higher gear ratios helps. I think a 3.73 would help me, but I'm not sure how many people are running a 3.73 with a T2R. I think 4.10s would make me borderline shifting to 3rd which I don't want to do.
I'll probably just keep my stock end for the time being. I've had decent success with it so far.
In this event, having higher gear ratios helps. I think a 3.73 would help me, but I'm not sure how many people are running a 3.73 with a T2R. I think 4.10s would make me borderline shifting to 3rd which I don't want to do.
I'll probably just keep my stock end for the time being. I've had decent success with it so far.
BTW I'm currently still on the stock differential but I will go to an auburn racers differential soon (assuming I keep the car :'(). There has been some quality issues surfacing with the Torsens T2R differentials.