which limited slip style?

[megaladon6]

what type of diff do you think will work best for a pro-touring/g-machine/whatever the hell you call it when you try and out-handle cops and corvettes? eaton truetrac, clutch, cone, whatever. it won't be at the drag strip much but it will be abused on the street.

it will be going in the ever popular 8.5in.
sub-question--did the GN's come with a non-posi. i shudder at the thought but i guess it's possible.

 

[KrisW]

The GN/s were all limited slip, but some were that horrible gov'loc (grenading style) differential and they suck bad!

I think the auburn clutch style is the best 8.5 posi unit. It is really tough and can take one hell of a beating.

On another note, I am finding that if you use a zexel-torsen posi from a 4th gen firebird/camaro, you can make the old 7.5 last a good long while. They look like a meat grinder when you see them, I haven't seen them for the 8.5 yet. With a set of custom axle shafts from Jeg's, I haven't broken one yet.

 

[85 Cutlass Brougham]

I think you are referring to what is called a "Helical" or "Torque Biasing" differential. It uses no clutches, but rather uses gears meshing in such a way as to lock up under certain circumstances. It would be the best in a street car or road race car but not in a drag car. In a drag car they are not as strong as other designs, and the added cost is not needed as a clutch style posi is more than sufficient. Also, yes. There are non posi G body 8.5's out there. I think it was optional on both the turbo Regals and Cutlass 442, but it may have been just one or the other.

 

[megaladon6]

the one i'm looking at is supposedly from an 84 GN with 3.42's and a non-posi. it has the square tabs on the bottom and an 11" cover and the right mounts so it sure seems to be a g-body 8.5 but i was thrown by the non-posi. i'll have to get out there and double check it.

for the diff, i will be mostly street driving it but i know i won't be able to control myself from doing burnouts.

 

[Chevyman85]

I have a personal preference for the Eaton type clutch style posi. It give you enough lock-up to get traction and leave "duals" And down the road they are rebuildable, unlike the cone type Auburn gears. I have installed 2 of them for street use and have no complaints.

On another note, a car without posi is only have the car... in my opinion at least!

 

[85 Cutlass Brougham]

Well, a helical is plenty strong, but just not the best for slicks and wheel stands. I would go with a helical as it has no clutches or cones to wear out.

 

[KrisW]

I was referring specifically to the GN; I know the turbo T's and 442s had to check that option off on the sheet.

Maybe your 84 rear was worked on once...

 

[megaladon6]

that might be it. some people think and regal with a turbo is a GN. speaking of which what is the first year of the GN?

i'm not going to have slicks by any means, i'm planning on 275/40/18's in back.

 

[Silent viewer]

first year for a true gn is 84(i think,99% sure) but there was also the 82 that no one seems to have heard of unless you are a guru like most of us.