A little idea of what I don't want. I ve got a nissan frontier with a limited slip diff. When I hit the gas on the straight line both tires go up in smoke and they both spin- no problems there. Coming rolling around a corner and punch the gas in the middle and one tire spins then the other and then the first. It sort of rocks back and forth and the rear of the truck shimies around the corner. I'd like a nice sweeping motion with my Barracuda. I like the bring the rear around on slow speed corners and ride them as far as HP will alow.
I've heard about air lockers that use a flip of a switch. Can these be flip on just before I punch the gas?
Do these need an air pump to operate or do they run off vacuum?
What are some cost estimates?
Are they made for 8 1/4 rears?

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67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir

That's how limited-slip diffs work.
Then...don't use a limited-slip!
Not applicable for streetgoing vehicles. They are for off-road vehicle service only, and are not meant to be switched on and off as you're flyin' down the road.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

What type of system would I need for this?

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67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir

What makes you think your Barracuda will drive like your truck? My '66 Dart with a clutch type limited slip in the 8 3/4 would burn both tires in a straight line or around a corner. I put the limited slip in to get better traction coming off turn 6 at PIR as I used to burn off the left rear on corner exit and it worked. What type of limited slip is in the Nissan?

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Joshua

There has been some mixed reviews here locally about using the ARB setup, some like the fact they can drive with an open diff on the highway, then while parked flip the switch and use it for drag racing...it is not a "shift on the fly" setup... Those that have complained about it, talk mostly about the setup, some have worn them out prematurely, and in one case the unit just failed to seal properly (thus making an expensive open rear)....


I only think it got popular because Ehrenberg wrote up an article and installed one in the "Green Brick" for a while....

-D.idiot

The Nissan got a clutch type LSD with friction modifier- what ever the means.
I am asumming that if I put the same type of LSD in the barracuda it would seem to me that theres a good chance of it acking like the Nissan's LSD. This is why I ask.

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67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir

Do they have the true-trac or torsen type limited slips for your app?

They don't have clutches or friction materials to grap (which means nothing to wear out, or no special lube too)

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

For one thing the Barracuda is a lot closer to the ground than the Nissan. The Barracuda will transfer less weight in a corner than the pickup and will not unload the inside tire so badly. The behavior your describe of the Nissan is more of a handling problem than a limited slip problem.

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Joshua

If the nissan had more power it would keep the rear end locked even when one tire gets lighter contact on the road. Clutch and cone type limited slips have pressure put on the friction surfaces by the spider gears trying to push apart, so with allot of torque a good one locks like a solid axle. Adding friction modifier can make them smoother on tight right turns, but they will lock better if you don't use any. It will not hurt the rear end but you will have to live with more chatter at medium throttle turns.

I would think that a supercharged (11psi) 3.3L thats putting out about 250 HP would be enough power to keep the rear locked. I do understand the body roll concept or at least the weight transfer concidering it got front and rear sway bars. Enough about the nonSlant product. I mentioned it as an illustration of what I wanted to avoid. If a LSD will not do this (as mentioned above) and give me a nice sweeping burn out in my Barracuda, then that'll work for me.
I understand the concept of how the friction and viscous diffs work but I don't have real world experience. What I am looking for is someone that does and can give me options and rough costs of each system so I can decide which way to go.
What different options do I have for an 8 1/4.
This car is not a daily driver but is driven to the beach and car shows. Planned HP is around 300. (please keep comments on diff)

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67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir

This is about the rear end, and how it could perform. You would think the nissan would have enough power, but from what you describe it does not. Torque really matters besides horspower. Since you do not want your slant to behave the same way you will need enough torque and horsepower to steer the car out of turns with the gas pedal. A cone or cluth type rear end with enough power driving it will work fine, this was my point. A detriot locker type would do this as well but they really don't drive that great on the street or the highway. A torsion/gleason type (the tru trac) would do it's best to keep both tires planted and is probably the best diif out there for high power - high speed handling. I looked a while back and it is not made for the 8 1/4. I am pretty sure they do not make the air locker for the 8 1/4, the only applications I have seen are for large rears used in trucks. You would have to get Something like a Dana 60 or ford 9" into you car. Even with a solid axle it is not a given that the rear end will lite up and power thru a turn smoothly. It could hop around or worse yet have both tires grab and push the car straight in whatever direction it is pointing. If it is having fun around low speed corners with the back end sideways you want, you could refrain from putting large sticky tires in the back. Of course gear the car to be right if the torque band at the speeds you want it to work at. I do have allot of experiance with high performance street cars that can do what you are talking about. 300 horspower should be enough, but in my experiance you will need at least 300+ ft pounds of torque as well. Save money by using a normal sure grip, and get all the power you can and a good torque converter.

ARB RD112, for Pre-96 Dakota, Dodge Trucks/Vans 27 spline 8.25" rears...

-D.Idiot

Great, could you find a 8 1/4 tru trac part number?? That's the one I said was not available, and I really wish it was. I have to admit the air locker is a surprise to me, I never found any when I was researching 8 1/4 options. I may have dismissed it though. They must be selling them to guys who off road in the mud, or just have to have it because its there. I would hate to see someone waste their time and money on a part that is not best (or any good at all) for the application. A normal limited slip will hold onto a slant just fine. With the air locker you have open rear or solid axle and nothing in between. With a 300 hp engine you would end up driving around frying the rear right tire all the time or trying to drive with it locked, and it's just not going to work or be fun. Actually pretty dangerous. See if you can drive or go for a ride in a car with a spool and it will all become very clear.

Air lockers make sense for off-road 4x4 use. Limited slip diffs can be pretty treacherous in snow ( I have disabled the Eaton unit in my work truck)....they tend to "push" in low speed corners. For low speed turns in 4 wheel drive a open diff is much prefered.....same for bouldering.
The air locker gives you the differential action you need for daily driving yet locks when you really need to turn both wheels (like axle deep in mud)
Air Lockers are just silly on a street car.....In fact any locker is.


Bren: Why not build the suspension and get the tires your car needs to handle properly? Lighting up the tires on turns may be spectacular but its definitely not efficient.

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Yeah....Im the one who destroyed this rare, vintage automobile.....