9'' or 12bolt( which one to buy?)
11-25-2006, 11:46 AM
#21
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I'm hoping a 12bolt should be enough for me. I don't really launch that hard, only about 3500rpms and I'm not making a ton of hp right now. Even with more grip and hp I figure the 12bolt should be plenty.
12-04-2006, 02:24 PM
#24
We use to use the Eaton Posi's with the 800lb springs. After several years of running, they start to do the one wheel spin deal. I'd go with the Truetrac, you also don't use any additive with them. Bob
12-04-2006, 04:35 PM
#25
Originally Posted by Exotic Performance Plus
We use to use the Eaton Posi's with the 800lb springs. After several years of running, they start to do the one wheel spin deal. I'd go with the Truetrac, you also don't use any additive with them. Bob
Oh well...
12-04-2006, 06:15 PM
#26
Originally Posted by MeentSS02
That sounds sweet...can't wait until mine does that Oh well...
Oh well...
12-06-2006, 01:11 PM
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I was kinda afraid that the eaton wasn't quite as good as the detroit true trac. It would be nice if moser wouldn't use 4 torque arm bolts. Where would I even get them at?
12-06-2006, 02:56 PM
#29
Originally Posted by BES Stroked Nova
12bolt all day long, 1.45 60ft in my nova with a stock case, filled with moser parts...
Why? I have a feeling the torque arm is flexing the housing. We don't encounter this problem with the 9 inch housings, most likely because they are beefier. Bob
12-06-2006, 03:28 PM
#31
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9" all the way. I put mine in with a tru-trac posi and 4.11's. I took it out and beat the hell out of it at the track. Like 6K dumps with slicks. It has never had one problem. I changed the fluid after the first year and everything inside looked brand new still.
If you want the strongest you can get then get a 9".
If you want to try to save a few pounds, you can try your luck with a 12bolt. But it seems hit and miss with the issues they have.
Also, I got my 9" for 1900 bucks brand new. And I had to paint it and assemble it.
And Bob, I think you might be right about the TQ arm on the 12 bolts. It seems to make sense.
If you want the strongest you can get then get a 9".
If you want to try to save a few pounds, you can try your luck with a 12bolt. But it seems hit and miss with the issues they have.
Also, I got my 9" for 1900 bucks brand new. And I had to paint it and assemble it.
And Bob, I think you might be right about the TQ arm on the 12 bolts. It seems to make sense.
12-13-2006, 01:50 PM
#32
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I would like a 9'' but I just feel my car doesn't quite need that rear. I'd like to keep weight down to a minimum for now. If I had more than 500hp it would be a no brainer,I'd probably just get a spool right away in it.
12-14-2006, 02:14 AM
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dont mean to hijack but what is the difference between trutrac and a spool? I dont know what they mean? Why is the tru trac more expensive? with the 9inch option.
12-14-2006, 03:31 AM
#35
Originally Posted by BirdmanLS1
dont mean to hijack but what is the difference between trutrac and a spool? I dont know what they mean? Why is the tru trac more expensive? with the 9inch option.
DETROIT TRUETRAC TORQUE PROPORTIONING DIFFERENTIAL
The Detroit Truetrac is the first gear type limited slip differential in the industry. Its’ patented design of parallel axis planetary helical gears provide a quiet, automatic splitting of torque. Power transfer goes literally unnoticed by the driver – even in front wheel drive axles.
The Detroit Truetrac performs like an open differential under normal driving conditions and automatically transfers torque to the wheel with better traction when ground conditions warrant. The limited slip responds instantly to torque feedback, anytime, at any speed.
ALUMINUM SPOOLS
Save weight without giving up performance. Moser offers hi-performance aluminum spools that weigh approximately 4 lbs. less than our steel spools. That doesn’t mean they are not as strong. In fact, the spools feature a thicker ring gear flange and large diameter mid-section for increased strength. Bob
12-14-2006, 04:09 AM
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9" is the way to go. They can also be built for pretty cheap. You can go buy a housing, and 31 axle package for $1k. Then pick you up a stock 31 spline posi rear end with decent gears for a couple $100 and go. It'll hold up fine to a Heads & Cam car. I have a friend that has a 69 Camaro with a BBC that ran 8's at 160mph on a stock 3rd member case. It wasn't until he really cranked up his nitrous leaving the line that he broke the case. Now he's just running a stock Ford "N" case and going strong. I know some people claim the stock cases can't handle abuse but i've seen them do it first hand. Just stay away from the WAR cases, they suck.
12-14-2006, 07:30 AM
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Hate to contradict but the true track just looks like an improvement on the old Torson-Gleason unit to me.
BTW, I love mine! Best posi I've ever had for a 9 inch. The bar for the 9 inch posi isnt set all that high though.:
58 pontic rear much better. Parts are too hard to find. Big Dana powerlock posi. Very strong and easy to vary stiffness. 55 Chevy rears use same kind of posi. I used to set mine up with 8 3/4 mopar clutches so it was practically tight as a spool. Cant find the posi for that rear. If a true track were available for that big 57-64 pontiac/olds, I'd use that rear in a second! Not saving any weight though.
Due to parts availability 9 inch is king! Long live the King!
BTW, I love mine! Best posi I've ever had for a 9 inch. The bar for the 9 inch posi isnt set all that high though.:
58 pontic rear much better. Parts are too hard to find. Big Dana powerlock posi. Very strong and easy to vary stiffness. 55 Chevy rears use same kind of posi. I used to set mine up with 8 3/4 mopar clutches so it was practically tight as a spool. Cant find the posi for that rear. If a true track were available for that big 57-64 pontiac/olds, I'd use that rear in a second! Not saving any weight though.
Due to parts availability 9 inch is king! Long live the King!
12-14-2006, 07:44 AM
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You are right about the WAR case. To make the stock posi work you need to Shim the springs in the pinion block and add an extra clutch. The way they come they turn one wheel wonder very quickly. I can't remember for sure, but I think I used an extra 1 sided clutch for that. I built one up for a friend and he loves it. You should use the 4 pinion case for that.
Also dont buy a stock ford posi that is out of a third member. The hat and body are machined together and can't be interchanged between units. you will never solve that runout problem.
New posis are available on Ebay for under $300. I believe they are made By Yukon. If you use this one you will have to grind down the pilot bearing housing some though. I don't like doing this. It weakens the housing. The stock cases especially the WAR case from the late 1950's are weak anyway. I have warped the bearing caps on a few of the later ones. C7AW i believe. There are some non nodular imposter cases out there that are not marked with an N but are actually nodular Iron. You just have to know what you are looking for. If you find a third member in a yard with the big pinion bearing, the chances are the case is nodular (ductile) iron.
Happy Hunting.
Henry
Also dont buy a stock ford posi that is out of a third member. The hat and body are machined together and can't be interchanged between units. you will never solve that runout problem.
New posis are available on Ebay for under $300. I believe they are made By Yukon. If you use this one you will have to grind down the pilot bearing housing some though. I don't like doing this. It weakens the housing. The stock cases especially the WAR case from the late 1950's are weak anyway. I have warped the bearing caps on a few of the later ones. C7AW i believe. There are some non nodular imposter cases out there that are not marked with an N but are actually nodular Iron. You just have to know what you are looking for. If you find a third member in a yard with the big pinion bearing, the chances are the case is nodular (ductile) iron.
Happy Hunting.
Henry
