LSD or not LSD, thats the question?
Discussion
Depends how you're going to drive it.
I fitted a Sierra Cosworth LSD to my S1, but in truth it's not powerful enough to massively overcome the grip, and in the event it does it then takes a while for the viscous diff to 'wake up'. Would make more difference in a V8, but then they all have them anyway.
As Mike said, values have changed too. I found the Cossie one a few years back for only £150, but then had to rebuild it, and then had to have custom driveshafts made as it's got 108mm flanges, not the 100mm the S needs. But on the flipside, the Cossie one is the correct 3.64 F/D ratio, where as most of the 100mm flange/LSD units are 3.38, which on a V6 might blunt the edge a bit on acceleration.
Apparently a 3.64 ratio 100mm flanged LSD is a real thing, but hard to source.
I fitted a Sierra Cosworth LSD to my S1, but in truth it's not powerful enough to massively overcome the grip, and in the event it does it then takes a while for the viscous diff to 'wake up'. Would make more difference in a V8, but then they all have them anyway.
As Mike said, values have changed too. I found the Cossie one a few years back for only £150, but then had to rebuild it, and then had to have custom driveshafts made as it's got 108mm flanges, not the 100mm the S needs. But on the flipside, the Cossie one is the correct 3.64 F/D ratio, where as most of the 100mm flange/LSD units are 3.38, which on a V6 might blunt the edge a bit on acceleration.
Apparently a 3.64 ratio 100mm flanged LSD is a real thing, but hard to source.
Kitchski said:
Apparently a 3.64 ratio 100mm flanged LSD is a real thing, but hard to source.
Pretty sure that's what I have, from a Scorpio Cosworth? But it's too cold today to go crawling underneath to check the "dog tag"!Certainly don't recall the speedo getting less (or more) accurate after I changed it
While you have your diff out and if you can get one at a reasonable price then I'd take the opportunity to fit one. 99% of the time you will not feel any difference, they give the car a more stable feel in the wet and if the road is a bit dirty. Oh and parking in a field at a show 
Best mod is to fit good new tyres
Best mod is to fit good new tyres
...are you sure it is not LSD...?
The reason is that I researched this a while ago for my S3C. The opinion was that the S3C "mostly" had them as standard to justify its price increase over the non C car...but you cant be sure.
Then there was the issue of how to test them: Apparently the type of LSD on TVRs was some for of oil based one which was a bit of a half-hearted LSD approach, and so turning various inputs and outputs by hand was not necessarily the best way to test for it. - Which is why I asked if you were sure.
I believe the ultimate check is to read the label on the tag on the diff and look for the magic letters "AA" which indicate it is LSD.
Good luck
The reason is that I researched this a while ago for my S3C. The opinion was that the S3C "mostly" had them as standard to justify its price increase over the non C car...but you cant be sure.
Then there was the issue of how to test them: Apparently the type of LSD on TVRs was some for of oil based one which was a bit of a half-hearted LSD approach, and so turning various inputs and outputs by hand was not necessarily the best way to test for it. - Which is why I asked if you were sure.
I believe the ultimate check is to read the label on the tag on the diff and look for the magic letters "AA" which indicate it is LSD.
Good luck
Maffe said:
Ignoring the cost, whats the difference in performance?
The viscous diffs drive pretty much like an open diff - and IMO are no better than having an open diff.Plate LSDs can vary enormously depending on the ramps and preloads used. If you have too much preload you may feel it binding when you're maneuvering round tight corners. Set up right, you won't be aware that it's an LSD in ordinary driving.
I've not driven an ATB equipped car but I understand they are much more linear and don't tend to suffer from stiction as plate LSDs can.
GreenV8S said:
The viscous diffs drive pretty much like an open diff - and IMO are no better than having an open diff.
May be they're not "the best thing since sliced bread" but presumably Ford thought they had something to offer, they wouldn't have fitted 'em just for the fun of it?possibly not the most scientific analysis but if I hoof mine out of a tee junction I reckon it's doing something, inside wheel doesn't spin away wildly
think I need some limited slip door locks
........ embarrasingyou have to remember these are a 'Road Car' LSD and not a motorsport LSD
they are set up 'soft' so are not that noticeable unless provoked.
It is possible to have them 'reset' to motorsport aggressiveness but costs lots (I paid £500 in 1995 to have one reset)
it then worked well in my rally Sierra Sapphire 4x4
I still prefer my S with the LSD rather than without
they are set up 'soft' so are not that noticeable unless provoked.
It is possible to have them 'reset' to motorsport aggressiveness but costs lots (I paid £500 in 1995 to have one reset)
it then worked well in my rally Sierra Sapphire 4x4
I still prefer my S with the LSD rather than without
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