Diffs - Lsd Or Not?

[chris-gti 14]

Hi all,

 

Firstly apologies for this topic as i'm sure the subject has been covered countless times before.

 

I know i'm not a regular on here but time has come to rebuild the gti again. This time with a VTS/GTI6 setup.

 

I'm looking mainly at my suspension and transmission as i want to get on a few track days this year as last year was a financial waste of time.

 

The question is really are limited slip diffs worth the money or am i best spending my money elsewhere. I've read up on the trans-x and the Quaife diffs and opinions seem really varied from person to person. The car is predominantly a road car and won't be running PAS setup.

 

I have befriended an ex-rally driver who drove 205s, 106s and 306s and came away even more confused after discussing not being able to hold onto it through hard cornering because of the lack of PAS, then saying he ran a few different LSDs and had good results with all, with or without PAS. Maybe too many beers were to blame.

 

What are everyone elses thoughts and experience?

 

also spotted this: http://www.ebay.co.uk/itm/limited-slip-diff-be3-4-box-/121063600215?_trksid=p5197.m1992&_trkparms=aid%3D111000%26algo%3DREC.CURRENT%26ao%3D1%26asc%3D14%26meid%3D5515625439344851564%26pid%3D100015%26prg%3D1006%26rk%3D1%26sd%3D121063600215%26

 

Thanks.

Chris

[Batfink 201]

Its the best thing you can do on a car in my opinion. Quaife is good for a fit and forget sytem

[Tom Fenton 1,525]

Agree with above, LSD is amongst the best mod you will make to the car. Have a search on the subject as there have been lots of discussion about the merits of the various diffs out there.

[allanallen 528 2 Cars]

Best mod for the money by far, I'd highly recommend a gripper LSD for road, track, rally, shopping, everything really

[chris-gti 14]

Thanks for the fast responses everyone. Looks like this is the way to go for me.

 

Best mod for the money by far, I'd highly recommend a gripper LSD for road, track, rally, shopping, everything really

 

Just read up on the gripper, quite impressed they have a lifetime guarantee and i'm always in need of a fast exit from the supermarket carpark. That's definitely the favorite from what i've looked at so far.

 

 

 

On a bit of a side note, is the gti-6 box worth using or am i best dropping my old 1600 BE1 in? I have roughly 10 BE1 and BE3 boxes from XU and XUDs which my step-dad has collected over his time as a citroen specialist along with an MI16 BE3 box and a 1900 GTI box from my own personal collection so the gearing combinations i could use are pretty vast assuming the gears are interchangeable? Straight line speed doesn't really interest me so a short box would be my preference.

[allanallen 528 2 Cars]

I've always found grippers customer service to be very good aswell, which goes a long way IMO. I prefer the way the gripper feels to the tran-x, just nicer somehow, better made and more settings available although they don't have the two sets of ramp angles like the tran x.

 

Best off the shelf gearbox for me would be the 1600 or the mi16 box. Depends what your using the car for really

[Alan_M 66 1 Cars]

I don't think it's been mentioned yet, the box needs modifying slightly for a Trans-X diff. Not a major job but you'll need a dremel (or similar) to shave a bit of the inner diff casing off. Superb diff, just a bit clunky at parking speeds!

[brumster 135 1 Cars]

I'm surprised at some of the advice, to be honest. You says it's predominantly a road car - I would hate to be driving mine around with the plate diff in it, although I guess if you set it fairly loose on the preload and use the 45/45 ramp angles their behaviour might be a bit better (less aggressive). But then why bother spending £500-600 on a diff for the occassional track day? I was very impressed with the Quaife ATB setup for a road/track car, and I think if I was using it day-to-day with occassional track use I'd look at that rather than a plate diff.

 

Don't get me wrong, the plate diff is the muts nuts for outright performance, but I'm not sure I'd want it day in, day out on a road car . What sort of power/torque are you putting out - do you have trouble putting it down right now? What sort of mileage are you doing - plate diffs do wear out (another bonus on the Quaife ATB).

[dcc 855]

Used an AP Suretrac diff for months in my road car, circa 160bhp - found it very pleasant to drive, and when giving it some grief it responded very well, exactly what you'd want from a diff. If I had the option between a t £600 quaife, £300 Suretrac id go for the suretrac - however, I do fancy trying a '3j Driveline' diff now that theyre available - an improved version of Tran-x.

[allanallen 528 2 Cars]

I'm surprised at some of the advice, to be honest. You says it's predominantly a road car - I would hate to be driving mine around with the plate diff in it, although I guess if you set it fairly loose on the preload and use the 45/45 ramp angles their behaviour might be a bit better (less aggressive). But then why bother spending £500-600 on a diff for the occassional track day? I was very impressed with the Quaife ATB setup for a road/track car, and I think if I was using it day-to-day with occassional track use I'd look at that rather than a plate diff.

 

Don't get me wrong, the plate diff is the muts nuts for outright performance, but I'm not sure I'd want it day in, day out on a road car . What sort of power/torque are you putting out - do you have trouble putting it down right now? What sort of mileage are you doing - plate diffs do wear out (another bonus on the Quaife ATB).

I guess different people want/expect different things from their cars, for me the 205s all about fun even when you're using it daily. I love my road going 205 with a 45/45 lightweight tran-x. It's running a non assisted 3.2 rack and it doesn't 'rip your arms off', 'try to kill you', clunk or anything. It'd definitely be better with pas mind purely for the steering damper effect on higher speed, rougher surfaces. im not saying you dont know it's there, it's much different to an open or quaiffe diff and alters the steering feel a lot, in a good way mind

The op should probably get in contact with local members and perhaps have a drive of their cars maybe??

[Tom Fenton 1,525]

I have got 205's with one of each type in, Mi16 track car with a Quaife, turbo road car with a Tran-x.

 

The Quaife is a nice and gentle thing in operation. However when it was fitted some 8 years ago the car in question was used 80% on the road and 20% on track. It now does very limited road mileage and goes to trackdays on a trailer, so a plate diff would probably be better, the Quaife is compromised when using it hard on track as it will allow wheelspin when hopping kerbs etc. Key difference, the Quaife is a TORQUE BIASING diff, NOT a limited slip. It requires compliant suspension to work.

 

The Tran-x in my turbo car is harsher than the Quaife, but on the lightweight settings it was perfectly usable even without PAS. The car in question has over 200ft/lb of torque and I'm fairly sure that without the plated diff it would be useless. I have been on track with it and it was awesome.

 

I suppose in summary you need to be very realistic about what you will use the car for. Primarily road and below 150ft/lb of torque I'd say Quaife. Primarily track, or road use above 150ft/lb of torque I'd say Plate (Tran-x, Gripper, etc.)

 

I have just purchased another Quaife diff to go in another of my cars, a standard roadgoing 1600. The Quaife will add loads and detract nothing.

[kyepan 291]

I agree with tom on the compliant suspension for the Quaife, really agressive toe, and or worn bits (front or rear) will manifest themselves as an unruly ditch finding grabby front end, been there, got the t-shirt. On the other hand, a mild fast road setup with bilsteins, eibach and sorted rear beam.. it's very easy to drive reasonably quickly and smoothly, with little or no drama despite putting down 160ft lbs at times. It will feel more capable and planted.

 

edit - Basically - don't set it too low, or the bump steer will get you.

 

It will also change the steering feel, you'll be able to feel the throttle through the wheel more and you'll be driving it more on the throttle to get the best out of it.

 

Fit and forget - I fitted mine in 07, and i've done nothing to it since, no complaints, great bit of kit.

Edited February 11, 2013 by kyepan

[chris-gti 14]

I feel i have opened a can of worms here, the car will be mainly used on the road on those sunny days we so frequently get... :S

 

I do like the sound of the fit and forget and my power output isn't going to be groundbreaking, aiming at a standard(ish) GTI-6 setup so from what's been said the quaife seems to me the better option. even with the 1600 on the road i did tend to get a bit of smoke off the inside wheel every now and again when pushing hard. I'll probably be running GTI-6 beam and KONI front struts with about 30-40mm drop springs.

[Tom Fenton 1,525]

I feel i have opened a can of worms here, the car will be mainly used on the road on those sunny days we so frequently get... :S

 

I do like the sound of the fit and forget and my power output isn't going to be groundbreaking, aiming at a standard(ish) GTI-6 setup so from what's been said the quaife seems to me the better option. even with the 1600 on the road i did tend to get a bit of smoke off the inside wheel every now and again when pushing hard. I'll probably be running GTI-6 beam and KONI front struts with about 30-40mm drop springs.

 

Can of worms? Huh? I'd call it a informative discussion from a number of folk with real life experience of the various options. As a prospective buyer personally I would call it very useful, but if you prefer can of worms then so be it.

[chris-gti 14]

 

Can of worms? Huh? I'd call it a informative discussion from a number of folk with real life experience of the various options. As a prospective buyer personally I would call it very useful, but if you prefer can of worms then so be it.

 

my apologies i didn't mean it to come across like that. I am very grateful for the input and it has been very informative. I meant the information coming across is more in depth than i anticipated with more possibilities. Maybe a can of worms was the wrong phrase. My use of sayings may be a bit out. English isn't my strong point.

 

there is a lot more to the plate vs. torque biasing pros and cons than I imagined. It is looking like the Quaife will be the best option for my application.

 

Once again I apologise if i offended, it wasn't intentional. Thanks everyone for your input.

 

Chris

[Cameron 16]

Another recommendation for an ATB diff from me; I would only fit a plate diff on a dedicated / heavily biased track car, just because of noise and maintenance issues.

[welshpug 1,622]

I haven't a clue what settings it had, but the plate diff in DrSarty's car (maybe miles could tell us, if not Rich himself if he's watching from afar)

But I really did not notice the diff at all when I had a quick drive of his 2.2 MI16, that is t say it was totally unobtrusive at town and dual carriageway speeds, I never put my toe down as it wasn't my car and it was dark and raining!

 

 

I Have driven DCC's car and also have no complaints, other than the bloody silly paddle clutch it had

[Miles 331 1 Cars]

As Tran X are no longer with us look at the 3j Driveline Diffs which I use and supply, still need a little fettling to fit but other than that very good,

I do have power steering but on mine the Plate Diff is fine on the road for the 250 miles I did to run the engine in, no knocks or bangs but I know some did, I used to run a ATB in my Dad's 306 and hated it and if I had bought it I would have been not very happy, The only thing I can say in a positive manner of them is they are stronger over the std Diff

 

The ebay link is just a Std Diff from 1995 as fitted to high torque/power models, Worth £50.00 if that

[brumster 135 1 Cars]

Kyepan makes a very good point - any worn or poorly adjusted aspects of your suspension will really show up on a hard-worked plate diff very important to get everything set up properly. You'll find uneven/poor road surfaces, or badly cambered roads, also have you 'focused' when pushing along. Again, not trying to put you off, but if you're hustling along and you've got the diff set to something agressive, you will need to concentrate a little (edit: if you've got enough power/torque to work it hard enough). If you're just pottering and/or have the diff set really loose then.... why bother with a plate diff at all? Great for track, great for gravel, great for ultimate no-compromise performance. And yes, I do have a plate diff in mine

Edited February 11, 2013 by brumster

[kyepan 291]

any worn or poorly adjusted aspects of your suspension will really show up

That was exactly what i was trying to get at yes, you'll feel like you're going to get spat into the gutter, or onto the opposite side of the road if you blink. The rest of the time if you apply power, it will go where it wants, and you end up steering around where the geometry is pointing the power, not where the road is going.

 

I would highly recommend getting your rear beam looked at and refreshed, then new top mounts, front wishbone bushes, rear sandwich mounts.. before you embark on a diff.

 

A simple cheap alternative to give you a more controlled corner exit would be a decent quality front strut brace, and a 24mm rear anti roll bar, probably half the price of a diff in total, and again a very sensible route to controlling the amount of inside wheel lift coming out of corners, and geometry going in.

 

I know this is a digression.. but again speaking from having been there (batfink can attest to this) we did a back to back test with a decent quality strut brace and it was more than noticeable.

[Alastairh 47]

Loved my tranx. As said keep your suspension, cv joints and gear box oil in tip top condition and you will enjoy it. I have been in friends cars with worn suspension and its been a head ache. I used it as a day to day car and fine.

 

Al

[Baz 421]

As above. Plate diffs every day are fine, if you're that worried then don't have them set up too harshly. Bedded in properly and not set up aggressively and they're not harsh or noisy.

 

I've used a Kaaz diff for the last few years in my 'daily' 205's without issue, it actually has made it more usable in snow/icy conditions. I also know of a few that have covered tens of thousands of miles without issue.

 

Getting out of that car & into my rally car with a Quaife was frustrating, they really do almost nothing in comparison.

ATB/Torsen diffs might as well be open diffs coming from plate diffs, they work but only to a point. I have no idea what you guys are talking about when it comes to shooting you off the road into the nearest ditch, that doesn't happen with ATB type diffs in my experience! (I have 2 Torsen diffs & 3 mechanical diffs currently) Drive an aggressive plate diff and you'll find that, but then that's the very point of them and means they're working!

 

Touch some damp/grass or lift a wheel with an ATB and it spins, less than an open-diff given, but they're nothing like proper mechanical diffs.

 

One of the best things i've ever done when it comes to competition use.

 

Suspension/geo should be kept in good fare anyway otherwise these cars feel crap in comparison, a diff just highlights issues, much the same way as any other chassis upgrades would.

[chris-gti 14]

Thanks for the input, i'm still on the fence weather to go ATB or plate. 90% of the front suspension components are new and the rear end will be modified to take the GTI6 beam. I've got a fair amount of time to think about it as i'm only collecting the donor '6 tomorrow and i have a lot of work to do to get everything stripped down to shell, i'm thinking about 3 to 4 weeks before i need to start looking.

 

I have no LSD experience at all so i'm going to have a read up on how the ramp angles affect the way it behaves and also look into upgrading my ARB and suspension bushes.