I keep hearing about these things and I believe they are only about a hundred bucks...

my questions are:

1 if I bought the take off posi, do you just install it on an open rear and you get posi? This seems a little to good to be true for 100 dollars.

2 what are the differences between this and a powertrac?

 

yep it's that simple. swap your ring gear set back lash and check the contact pattern.

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ICON Motorsports

1st & 3rd
MM Black Diamond 538 F&AM

 

yes its pretty simple actually. get new bearings pressed on it and go.. keep in mind it is a 3 series carier. it will accept any gear 323 or higher. i puttin my in hopefully next weekend

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91 camaro RS
- 305 TBI
Mods: Performer TBI intake, 1" TBI spacer, K+N, jet fan switch ,160 thermo,Accel control module, Jet Stage 2 chip, edelbrock TES headers, Compleate 3" Flowmaster exhaust, Edelbrock springs, KYB struts and shocks, 700R4 built by TSI, SLP tq converter, b+m trans cooler, white guage faces, megashifter..
next month: spohn LCA's and panhard rod, BMR relocation brackets, 323 gear

 

I ordered the take off also, I have the 3.73 gears on the way hopefully (paypal doesn't like my checking account )

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, Jon (350 TBI!)
91 Red My website

 

They come with bearings pressed on them, but SLP recommends changing them because other carriers may have 'bumped' into them. I re-used their bearings with a fresh set of races with no probs.

 

You gotta have 28 spline axles too!

 

Can the bearings be treated like those in a brake rotor- tapped out, and tapped on? Or are they more delicate?

Thanks!


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-Tom P (Hot rodded 1986 Firebird 2.8l) from http://www.f-body.net/mailbag/3rd/3rd_mailbag.html message boards
---Think your car could be pic of the week? Visit http://www.f-body.net for details!

 

You need a puller to get them off, they are pressed pretty tight. You could tap them on, as long as you are driving on the center of the bearing and not on the cage. Another trick is to use a propane torch to 'warm' them, thus loosening the press fit. But not going crazy with the flame to ruin the heat treat on them. I once used a piece of heavy wall pipe to drive a head bearing on the pinion.

 

How much power can these posi's handle? I want to put one in my 79 malibu instead of trying to find an 8.5" rear. I know I have to get aftermarket 28 spline axles and a ring and pinion set. Does anyone have any other advice, other than to buy and F-body (currently looking for one)?

 

I'm not 100% sure of the hp rating, but the torsen isn't made for serious shock loading (off the like slicks kinda sh:t)...

But what they are good for is road type handling. I mean, a regular posi is always locked unless the torque difference between the two axles is so extreme that the clutches start to slip. This IMO would promote some amount of understeer, although I have no source or test data (I just put 2+2 together)

If you are going to run a serious (I mean nasty super high stall TC or clutch dumps starting near my redline now...) I would say to sway away from the torsen... unless you get the HD torsen or the auburn ($$) and thats the reason that they are takeoffs from SLP.

Alot of people said they ran serious amounts of power through them, but I didn't do this first hand. I'm building a quick 355 geared nice (3.42) and setting it up for handleing and top speed since I miss this from my 'bird (4.10's and auburn pro posi...)

I could definatly vouch for the auburn, I beat that thing to hell and back, but the clutches will eventually wear and the lockup will suck... but the auburn retains 100% lockup for the life of the unit...

Depends what your after I guess, but I couldn't resist the $70 price tag on them.

Check this... http://www.torsen.com

 

I think hot rod magazine did an article on differentials about a month ago. They said that "cone style" limited slips aren't made to handle gobs of horsepower (that's what the Torsen is). They said good things about Eaton's positraction system, which I think I'm going to get.

 

TonyC, check your data.

The torsen is a gear-driven differential and there are no clutches, cone or otherwise. Auburn uses cones, Eaton uses plates, Zexel (torsen) uses gears.



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1982 Z-28

See http://www.mycar.net/mafb/registry/detail.cfm?id=276 for details

 

Great! Thanks, Joel!

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-Tom P (Hot rodded 1986 Firebird 2.8l) from http://www.f-body.net/mailbag/3rd/3rd_mailbag.html message boards
---Think your car could be pic of the week? Visit http://www.f-body.net for details!

 

Yep, thats the greatest thing about the torsen is it works 100% for the life of the unit without wearing out like the clutches. But the auburn is a cone type and was recommended to me for what I was after (good lockup first and decent street manners...) so I wouldn't say that it's junk at all, the only gripe I have about it is it isn't rebuildable. Auburn was thinking of doing in house rebuilds of their units but I'm not sure if they started that program yet. The gov-lock should never be used for performance, just for 'snow' driving as it is very breakable.