New type Locker/Limited Slip

[mgb260]

Here is a possibility for a locker/limited slip for the MGB rear. Actually any rear. I e-mailed him on price. I was doing research on the Cadillac 4.9 and came across Bud's Outback in Tuscon,AZ. He custom makes these lockers. His website is GR8grip.com.He E-mailed back and the price is $550.Here's the pics:

[roverman]

Ok, I don't see any additional gears or frictionals ? How does it lock ? It "looks" like the steel blocks just press against the axle/spyder gears ? roverman.

[mgb260]

Roverman, The springs against the side gears limit differential action .The strength of the springs determines how much. If the spring pressure could'nt be overcome it would work as a locker.The Phantom grip works the same but does'nt have the blocks going the other way. The Phantom Grip blocks start moving and wearing and you get more clearance and weaker spring tension.Plus it is only available for the earlier pre 67 Banjo axle. This design prevents the movement and wear plus ties it alltogether. It also adds strength to the spider gears similar to 4 pinion (cross) compared to 2 pinion open differential. Usually twice as strong.Remember the MGB 67-80 Salisbury tube type only has the Quaffe(very expensive) LSD available for it. I would use metal side gear shims instead of the fiber ones also. Under higher HP the fiber washers don't last very long.Most of 67-80 tube type(Salisbury) rears that I've heard about have blown the spider gears. This would probably prevent that. Here is a pic of the Phantom Grip for comparison.

[NixVegaGT]

I wonder how long the shims work? I would think they would wear out fast. Maybe not... Interesting idea.

[MGBV8]

"The springs against the side gears limit differential action"

With no clutch or frictional material, like Art  mentioned?  Just metal grinding against metal, then suspending in the diff oil?


Has this product been race tested? Is there any real world usage examples that you can point us toward?

I am of the opinion that the Phantom Grip is not worth installing. I would love to be able to bolt in an easy solution to my stock B rearend that is priced reasonable.

[mgb260]

Carl, The blocks work as bearings against the gears,the springs keep the tension. They are probably aluminum alloy. He has a website: GR8grip.com. Just stumbled on it because he does work with the Caddy aluminum V8s(Bud's Outback Automotive ,Tuscon AZ)

[BlownMGB-V8]

Old Ford street racers used to install extra shims in the diff, which had two halves that bolted together, and by doing so caused it to bind up and act something like a posi.

But having had a few posi units apart and having seen first hand what hard use does to one I've got to say that this ranks right up there with throwing money in a rat hole. If all you want is a little more traction in the snow and you otherwise never spin the tire (s) it might be OK. But with no clutches it isn't going to do much except increase wear on the side shims. Those kits that replace the side gears. Something like a Lock-Right would be much more effective.

Jim

[roverman]

Not knowing squat, personaly about this MGB, ring gear carrier, perhaps a dumb question is in order? Swapping-in a similar dimensioned, oem posi from  something else. Tons of small, posi carriers out-there.Perhaps some minor re-machining, or none? roverman.

[NixVegaGT]

That's a good point, Art. What size is the MGB ring gear?

[BlownMGB-V8]

I think it's right at 7-7/8". But it's been awhile since I measured one.

Jim

[roverman]

I'm thinkin, some basic dim's required for potential swaps. Ring gear I.D.,/off-set,carrier width/bearing journal dia.,bolt pattern for ring gear. There "might" be a posi, out there, quite doable."1 is the loneliest burn-out",  roverman.

[MGBV8]

It would be worth pursuing. Lot's of MGB owners would like a reasonable alternative to the ridiculously priced Quaife.

I'm not aware of anyone finding something close enough to mod to work......yet.

[BlownMGB-V8]

Maybe you could cut/drill an 8" ford or a D44 to fit without weakening them too much.

Jim

[roverman]

Untill   "someone", provides some basic dim;s we will remain,"slipin a wheel". Vega-Nic? Dana #30? Finding the right "splines" kinda important.  Anybody-we're slippin away here !  roverman.

[mgb260]

I think Jim hit the nail on the head when he sugested the 4X4 type that does away with the spider gears altogether. I found out a while ago that MGB 29 spline (Edit: MGB is actually 25 spline) are the same as AMC Model 20 29 spline. Problem is it is bigger than Dana 44. If you took the side gear plates for a Model 20 and the center part of Dana 30 (about the right size).No drilling just trimming down the side gear plates to same diameter as Dana 30 to fit in case.Some shimming probably for width.This is assuming same manufacturer same tooth pattern on driver. The driver gear teeth go all the way around on a Dana 30.  Why are these called lunchbox lockers? You could maybe get Jeep one piece type axles made also being that is the same spline.Don't get all mathematical on me now. LOL.

[roverman]

Ok, So "Lock Right" works like a "Detroit Locker"/ratchet type ? All gears or side gear plates are likely too hard to machine,need grinding or annealing to make machinable/ and re-heat treating. roverman.

[Dave]

No problem to grind. Might be too harsh for regular street use though. I'm interested.

[mgb260]

Actually they are supposedly smooth,you might hear a slight clicking in the parking lot driving slow while turning sharp. I wonder if the manufacturer would sell the Dana 30 one with the AMC Model 20 side gears. The first question to ask is if the mesh of the side gears and driver are the same on the two units. The Aussie Locker and the Lock-Rite appear to be the same design but, competing companies.Yukon gear just came out with their Spartan Locker also. Here are pics of the Aussie and Spartan:

[Dave]

You have read my mind.

[roverman]

How do we like the year, so-far ??

[Moderator]

Remember the MGB 67-80 Salisbury tube type only has the Quaffe(very expensive) LSD available for it.

Sorry guys, I'm having a hard time keeping up with all the activity around here.

Here's another company that makes limited slip differentials for the MGB. They're not a low-cost option, but if someone were determined to keep their Salisbury and they didn't want a Quaife... I know a couple people who are using Tran X differentials in smaller race cars such as MG Midgets.

<a href="http://www.tran-x.com/diffs/mgc.html">Tran X plate type LSD for the MG Salisbury axle.</a>
(Read the fine print. The title says "MGC", but the fine print clarifies that they work for MGB too.)

<a href="http://www.tran-x.com/diffs/index.html">This page explains the theory of operation.</a>

Notice that these are adjustable, and can also be bought for MGB with four different initial settings.

[MGBV8]

You're right Curtis, at $1240 + shipping to the USA, that is definitely not a low-cost option.  I'm pretty sure I could build a Chevy or Ford rear for less than that.

I was hoping we might stumble upon something reasonable that would work in the Salisbury.

[roverman]

Com'n folks, We know how this works. Feed us some "dimensions". What's the "diff"? Then we scrounge. roverman.

[v8ian]

Just as another thing to throw into the mix, I use a mid 80s Toyota Celica LSD axle, the shafts are bigger than 8" fords, and IIRC the outer bearings are the same too, possibly the Toyota PCD is the same as MG,  Supposedly good for 600hp on slicks, mine has never let me down and its ad PLENTY of abuse

[MGBV8]

Well, mine's all together under the car AND the garage is cold! Hmmm,  maybe at Pete's next weekend.....