Thread: I want Posi!!!

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I'm thinking about changing my differential over to Posi with a Detroit Locker. Anybody have any experience/suggestions about that? I just want to leave some decent burnout marks, ya know?

Do IT!

what rear end do you have. if it is a ford 9", just buy a limited slip center section from a junkyard, the autoparts store or speedway motors have them.

a lot of fords have posi type rear ends in them look at ford vans and truck the detroit locker i do not like a lot WHY i have one. this was the only way i could go with 35 spine axles and did not run a spool so with the detroit if the car starts to spin the tires you can not get back on it with out braking some thing like in my case 2 gear sprag in a 400 trans and this was a 36sprag the ford stuff work good with new parts in them have used may a set them up for many cars

Yup, what Pat said. The Detroit Lockers are second only to a spool for drag racing, but in street use a limited slip is a bit less harsh on the rest of the drive train. What type of rear do you have in the Effie????

I would be using it on the street. The rear axle is out of '62 or '63 T-Bird, so I was told years ago. It's a drop out pumpkin, 10 bolts holding it on.
8 3/4 or 9" ? I'm definitely no expert on differentials. It has the original tag, which doesn't match up to anything in the books I have.

Sounds like a 9". If the bottom two bolts on the center section have to be removed with a wrench instead of a socket and ratchet it probably is. Got the numbers off the tag??? Friend of mine has a bunch of old Ford ID books.

The lower two bolts would take a wrench, the housing drops down in front of them.

The tag reads:

C2SA4001VED___403
3.00___________2DA

I could be wrong on the 5th digit of the top number, the tag is bent there. It kind of amazes me that the tag is there at all, after all these years...

I'll see if I can track him down tomorrow if no one comes up with your answer before then. By the tag it's a 3.00:1 gear ratio.

all the old t birds had 9 inch s in them they are war cases in them they look like N case but no N and they are cast out of gray iron the one i had were this way and yes the gear is 3.00

just go with a limited slip carrier.....if you lock it completely with a spool or a detroit locker...the weakest link in the drivetrain will fail....best to use something that will last and be easy on the other parts......not sure of your combo but if the motor is fairly stock, and the trans is stock or mildly worked over then stay with a 3.23-3.42 area of gear.....good for making a sacrifical contribution to the tire gods.........and cruise friendly with a seat of the pants feel to them.

You know, i dont know how well you guys would do on the 4X trails. If you want streetability and the ability to lock the rear end, why not go with an Air Locker? Vacuum actuated, you can unlock and lock it as you please. Their a bit more expensive, but the streetability pays the difference

You guys are really helpful.
I have a friend that owns a vintage wrecking yard, maybe I could get a limited slip there. Will any Ford 9" posi pumpkin fit? Or are there year model differences? Like bolt pattern, yokes, axles?

I have a friend that owns a vintage wrecking yard, maybe I could get a limited slip there. Will any Ford 9" posi pumpkin fit? Or are there year model differences? Like bolt pattern, yokes, axles?

uhhm.......straight line for me guy.........with a bit of cruising....why not airlocker...?......in my opinion too many parts to fail when you when you hit it with 400 to the wheels.......simple and strong is my opinion for a decent rear......i personally dont know any of my race friends who use a air locker or even mention of an air locker. I have had very good luck so far with an auburn posi in my car....knock on wood....it has'nt let me down yet.