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Discussion Starter #1
So I was digging for an LSD for the Unot Turbo (Gertie said it can fit the TS box).
And I came across this.
This is from a Supra and was apparently fitted to a Uno as well.
Anybody EVER see this type of LSD before?
It really does look too good to be true kind of setup.
 

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the way I understand that, is its just two plates pushed against the outer gears by springs?! surely not?!

so its a bush mechanic friction type LSD, but the friction surface is not designed to be a friction surface. made out of inappropriate materials and is likely going to wear at a prodigious rate making LOADS of metal filings in the diff oil. So okay if youre happy to sacrifice your diff components regularly and replace, that's one thing in a rear wheel drive supra. But in a transaxle where the oil is shared with the gear box - the crap is going to go everywhere and ruin the whole transmission?
 

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Discussion Starter #4
So after a more in depth digging, these are actual items you can buy off the shelf overseas.
The thing is most of them use a softer metal (copper of metal alloy) to aid in saving the diff and not hurting the box (softer metals do not do damage I read :cheese:).
I like the idea, but you have to change your oil frequently and have to change these parts (hex LSDs never needs changing till they break).
I guess this thing has some merits.
I am half way interested if this will actually work at all...
 

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presumably, as wear occurs the friction contact surface will actually increase, so the degree of lock-up will increase?

yes, I see where you are coming from, if you use a soft metal and change oil regularly that's maybe okay on a rear drive set up where its diff only in the housing. but in a transaxle with shared oil...:paranoid:
 

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Discussion Starter #6
yes, I see where you are coming from, if you use a soft metal and change oil regularly that's maybe okay on a rear drive set up where its diff only in the housing. but in a transaxle with shared oil...:paranoid:
I'm not disputing this, but I am wondering if it will work within the relative safety limits. I am so tempted to try this out you have no idea. Anyone have a spare box they want to trash, lol! :cheese:
 

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Clearly, that is a solution to a question that should never have been asked...

There are correct ways of doing things and wrong ways of doing things. Let's look at it this way:

Would you replace your brake pads with steel blocks?
Would you change it to copper because it will be softer on your discs that steel?

Let me ask another question:
Do you plan to stop?

Such mods will work in racing or drifting applications but are seldom good enough for driving on public roads. I admit I need to wrap my brain around the operating concept of this system, but to me it looks as if it has been designed to destroy your diff as well as gearbox. From shafts to clusters to gears to bearings. Everything at once...
 

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I can't envision how it work...video, I need a video.
 

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I am half way interested if this will actually work at all...
It is called Phantom Grip LSD. It is a retro fit to your own diff

Phantom Grip Limited Slip Conversion Kits for open differentials. Products. Limited Slip Differentials · Xtreme Series Limited Slip Differential Units · Spring Upgrade Kits. Maximize the handling potential of your vehicle with the Phantom Grip Xtreme

And yes it works for a bit, but it does wear out itself AND the spider / planetary gears. I see it does have a conditional lifetime warranty, provided you get an expert to install it... :paperbag:

My cousin's brother-in-law used it before and does not rate it worth the money...
Streetracing.co.za ? View topic - LSD Diff FTMFW


ADDITIONAL:
This conversion does not add strength to the diff... Only provide some margin of slip limit
 

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Discussion Starter #11
Yup, I have seen and read all of those. There is a Honda with 750bhp that is currently running it for 5 years and another (for get the brand) with 500bhp running it for two years. I'd rather save up and do it properly, but I am seriously intrigued by the design. I really have to give it to the designer.
 

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Discussion Starter #13

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There is a simpler solution. The S shaped spring plate performs the same function: http://image.carcraft.com/f/9256030+w750+st0/116_0705_04_z+ford_8.8_rear_end+traction_lok_limited_slip.jpg
Yeah, seen that, but surely it would have the same effect?
Plus I would need someone that knows what the strength is of the "spring".
What about wear? I saw these, but was worried about them "floating" in the diff as well.
Yeah the effect is the same. I'd rather go for the four spring thing as the S-spring will bend more on the tips, rather than the curves, thus have an unequal force on the spider gears. That said, I won't be using either any time soon... I'll stick to either torsen or plate LSD
 

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I can't envision how it work...video, I need a video.
When you go around a corner the outside wheel has a longer distance to run. The spider gear connected to that wheel's sideshaft wil turn 3x faster than the gear connected to the opposite wheel. The two plates is pressed apart by the springs and rest against inside of the two large gears of the spider gearset. The gears will turn at same speed in oposite directions. Friction between the gears and plates brake the spider gears action. It is the same way an LS diff work, with the difference then you have friction material that rubs on each other.

As was said the parts will eat into each other. From my experience the soft steel will eat the hard one (the gear). How good the action will be is hard to say, steel trying to seize on another piece of steel with lots of oil in the mix?? It is possible that the shavings is microns thick, like the bits off a bike clutch, that also mix in the common engine/gearbox oil. only not steel. I will easily try that in a drag or race car that is not used on the road, meaning limited distance driving. But I am a stingy pensioner.

I know of a VW tuner that tighten the spider gears, in drag cars, in a way that there is interference between the spider gears and thus not easily turning. Another example of not so clever engineering that may work short term. That said Torsen does the same in another way............
 
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