LSD - talk to me

[Chip-mk1]

Ive not done knockhill so will bow to your experience of that particular circuit, I personally only find grippers drastically beneficial on very bumpy surfaces which isnt normally tracks but I do know knockhill is quite unique, so perhaps its best considered more like a rally stage, where I would want a gripper by a margin.

And like Phil says, I cant imagine there is really much time that you are actually up on two wheels and need to apply the power but cant, must be very momentary TBH.

With regards to value, quaiffe requires no maintenance, this helps residual values, I genuinely believe most people get a bigger percentage of outlay back on the quaiffe than gripper, although on CS where people are a little more naive that other circles I move in, maybe not I guess!

 

[MG cup]

Most cars are on two wheels at Knockhill because the rumble strips are all cuttable - that's fairly unique from my experience of circuits. The ones at cadwell certainly aren't, and hitting a few at brands nearly put me on my roof lol. The ones at anglesey that you can go wide on or cut are virtually flat, more like mesh than rumble strips. The actual rumble strips are fairly big and you loose speed hitting them as they destabilise the car IME.

Also even at knockhill you're on two wheels at the point of the apex, and only briefly. You shouldn't really be applying power at that point - you'd be applying power as you're coming out of the corner.

I think if I hit every bumpstrip everywhere on the circuits I do - I'd have a lot more problems with bent wishbones/wheels/track rods than I would the diff not letting me put the power down on 2 wheels lol

Not true, Duffus, Clark's and the Chicane especially your on two wheels with the power on for a reasonable length of time if your attacking, thats where a locked diff gains you time. Every kerb is cuttable that's right but the sausage kerbs are the track limits at KH even though you ride them at the chicane and you always have two wheels on the circuit if you stay away from them except the chicane entry sausage kerb which you can cut and stay on the circuit.

Theres a lot of kerbs that can be cut down south, most are the serrated type (dont cause damage) which are called reverse vallelungas iirc. Just look at BTCC or any one make FWD series they're bashing the kerbs like mad.

 

[Cup_Phil]

Not true, Duffus, Clark's and the Chicane especially your on two wheels with the power on for a reasonable length of time if your attacking, thats where a locked diff gains you time. Every kerb is cuttable that's right but the sausage kerbs are the track limits at KH even though you ride them at the chicane and you always have two wheels on the circuit if you stay away from them except the chicane entry sausage kerb which you can cut and stay on the circuit.

Theres a lot of kerbs that can be cut down south, most are the serrated type (dont cause damage) which are called reverse vallelungas iirc. Just look at BTCC or any one make FWD series they're bashing the kerbs like mad.

I had a quick look through my btcc/porsche/mini/ginetta footage from when I was up there and I agree with you for knockhill now tbh.
It's rare you ever need to apply power on two wheels but the configuration of KH there are some sweeping corners that are IMO designed entirely to keep you on two wheels through the corner. It's very orientated to be a crowd-pleasing circuit.

Their are a lot of kerbs you cut on southern/midlands tracks - but they are usually off-power cuts, or mid-power cuts. BUT I must admit you've now got me wondering if the only reason I'm off power over those rumble strips is because of how unsettled the car is without a diff and because I can't put the power down. Especially the S before the main straight at Donington - my mate with a diff seems to be able to push power on right through the S whereas I coast through off power and then apply it when the car has settled down again on the other side.

 

[NorthloopCup]

I can get all 4 wheels off the ground at Pflanzgarten at the nurburgring! Lol! Probably doesn't count though!

 

[Cup_Phil]

I can get all 4 wheels off the ground at Pflanzgarten at the nurburgring! Lol! Probably doesn't count though!

Hahaha yep!

 

[NorthloopCup]

Hahaha yep!

Thought as much! Lol

 

[Ph1 Tom]

I've never done KH but eslewhere I've not had issues with kerbs. Mine mainly gets road miles anyway.

 

[Chip-mk1]

I can get all 4 wheels off the ground at Pflanzgarten at the nurburgring! Lol! Probably doesn't count though!

It seems a lot smoother than it used to be there. I think with resurface work or some thing they have smoothed it out a bit?
seemed to get a lot more air half a dozen years ago then I do now.

 

[Cup_Phil]

They did - they took a load of height out of it because a few people disappeared into the woods lol

 

[NorthloopCup]

It seems a lot smoother than it used to be there. I think with resurface work or some thing they have smoothed it out a bit?
seemed to get a lot more air half a dozen years ago then I do now.

Yeah it's had a bit of remodelling I think mate, but its definitely had resurfacing. There's a few bumps that have disappeared (apex at schedenkreuz) but some have appeared (hatzenbach using kerbs and inbetween Pflanzgarten 1&2 is a nasty hump that throws the car over to the right as you turn in for Pflanzgarten 2 - NOT NICE!! Arsehole twitcher) but I get more air at Pflanzgarten now than I ever used to, but I am carrying a lot more speed.

 

[Chip-mk1]

Yeah it's had a bit of remodelling I think mate, but its definitely had resurfacing. There's a few bumps that have disappeared (apex at schedenkreuz) but some have appeared (hatzenbach using kerbs and inbetween Pflanzgarten 1&2 is a nasty hump that throws the car over to the right as you turn in for Pflanzgarten 2 - NOT NICE!! Arsehole twitcher) but I get more air at Pflanzgarten now than I ever used to, but I am carrying a lot more speed.

Its interesting the way that that the track continues to evolve in small ways like that as well as when it loses big chunks.

Speaking of wish when watching "Rush" and it was mentioned that Lauda got had round in under 7 minutes, I know that at the time it was 2 miles longer than it is now, I wonder what a modern F1 car would get on the shorter circuit we are all used to, WELL into the 5s I would think? (used properly I mean, not on some exhibition lap!) or is a 4 even possible?
Bellof did 6:11 in a 956 porsche 30 years ago, surely a modern F1 car would take a massive massive chunk out of that?

 

[NorthloopCup]

Its interesting the way that that the track continues to evolve in small ways like that as well as when it loses big chunks.

Speaking of wish when watching "Rush" and it was mentioned that Lauda got had round in under 7 minutes, I know that at the time it was 2 miles longer than it is now, I wonder what a modern F1 car would get on the shorter circuit we are all used to, WELL into the 5s I would think? (used properly I mean, not on some exhibition lap!)

Karousel and mini karousel would be, erm, interesting to say the least!! And don't even start me on Pflanzgarten 1&2! Lol! I think low 6's but not sure they would get into the 5's, but nevertheless I'd love to watch it! I see Porsche have done a 6:57 in the 918 as well. Boring lap to watch tbh, but looked a handful at the same time if that makes sense?!

 

[NorthloopCup]

You seen the in-car footage from Derek bells 956 when bellof comes past in qualifying trim?! Lol! He passes bell like he's stood still and bell does a sub 7 lap!! Flol

 

[Chip-mk1]

Karousel and mini karousel would be, erm, interesting to say the least!! And don't even start me on Pflanzgarten 1&2! Lol! I think low 6's but not sure they would get into the 5's, but nevertheless I'd love to watch it! I see Porsche have done a 6:57 in the 918 as well. Boring lap to watch tbh, but looked a handful at the same time if that makes sense?!

quickest porshe was bellof doing a 6:11, and I find it hard to believe an F1 car wouldnt be very significantly quicker, but like you say it depends on how it could be setup for some of the bumpier bits, when I was talking of 5s or even the possibility of a high 4 (sounds ludicrous but these cars are a LOT faster than a 30 year old porsche 956) I was talking more in terms of if they went back there as a circuit and developed the cars for it rather than just turned up with one, if that makes sense?


Lauda did under 7mins in 1976, and that was on a 2 miles longer circuit (ie an extra 15% or so) so that implies that his 76 car would do the ring we are used to in more like 6 flat.

He did Monaco (picked because its so similar now to then for comparison) that year in 1:30 ish, and a modern F1 car does it in more like 1:13, so would lap him every 4 laps he did!

So if it could do the same at the ring, he'd be doing 6 minute flat laps while getting lapped every 4 laps by a modern F1 car doing low 5s or high 4s.

Its hard to comprehend TBH!

 

[MG cup]

Knockhill is pretty unique in a way being that all corners are the type that will pick the wheels up but there's corners down south that are exactly the same. Brands for example.... Paddock hill - similar to the first part of Duffus dip, clip the apex and your airborne, (not John Cleland airborne mind) Bottom of graham hill - maybe only half a second air at a time but it all counts.

I can't think of any circuit that your not airborne at one corner at least in a FWD car, you have to be nice to the kerbs in RWD cars like Porsches, Ginettas and GT cars. Even Thruxton you get air at the chicane.

The Nordschlife is a different ball game all together, for sure a Gripper would knock seconds of the lap time.

If you mean the Donnington chicane Phil? then have driven it but watched far too many races and it looks like you need to scrub off all your speed on the straight and have the power on at the first apex if not earlier for a good run down the straight.

 

[NorthloopCup]

quickest porshe was bellof doing a 6:11, and I find it hard to believe an F1 car wouldnt be very significantly quicker, but like you say it depends on how it could be setup for some of the bumpier bits, when I was talking of 5s or even the possibility of a high 4 (sounds ludicrous but these cars are a LOT faster than a 30 year old porsche 956) I was talking more in terms of if they went back there as a circuit and developed the cars for it rather than just turned up with one, if that makes sense?

Yes mate makes perfect sense in that respect. If the car was developed with the ring in mind a 5 min lap time is a real possibility, but imo I only think it would be a mid to high 5 min lap. The ground effects that the grp c Porsches were running were significantly helping their lap times as well. The Tag Porsches were running in the regions of 1200hp in qualy trim as well weren't they?

Just googled and they were 700-750hp in race trim. No info for qualy trim.

 

[Chip-mk1]

Yes mate makes perfect sense in that respect. If the car was developed with the ring in mind a 5 min lap time is a real possibility, but imo I only think it would be a mid to high 5 min lap. The ground effects that the grp c Porsches were running were significantly helping their lap times as well. The Tag Porsches were running in the regions of 1200hp in qualy trim as well weren't they?

I do know that a modern F1 car is a good 15 seconds a lap quicker at Spa, (so like being about 45 seconds quicker at the ring) than a modern le mans car, I dont know how the modern le mans cars compared to the 956 though, as obivously a lot of rule changes since mean that they are less powerful now than they were then.

 

[Cup_Phil]

Paddock hill at brands? If you clip the apex on that and end up on two wheels you'd be f**ked! I don't think any diff would save you with the drop! LOL

Yeah the donington chicane you're absolutely right - hard on the 4 pots coming up to it, off the brakes, turn in and the guys with diffs are on the power right through the chicane. I have to come off the brakes, turn in and feather the throttle until the car is in a straight line on the straight - then power back on. Loses seconds through their behind my mates EP3 with a diff

I tried applying a bit of power through the chicane but the front wheels light up and you understeer off the right side of the straight lol

 

[JackJack]

What maintenance do the gripper need?

 

[Chip-mk1]

Paddock hill at brands? If you clip the apex on that and end up on two wheels you'd be f**ked! I don't think any diff would save you with the drop! LOL

Yeah the donington chicane you're absolutely right - hard on the 4 pots coming up to it, off the brakes, turn in and the guys with diffs are on the power right through the chicane. I have to come off the brakes, turn in and feather the throttle until the car is in a straight line on the straight - then power back on. Loses seconds through their behind my mates EP3 with a diff

I tried applying a bit of power through the chicane but the front wheels light up and you understeer off the right side of the straight lol

Even with the quaiffe though you can get back on the power at lot sooner at the chicane, its ONLY when you have a front wheel off the ground that you cant start laying down more power than standard, the moment the tyre is even slightly in contact the diff works again,

 

[Chip-mk1]

What maintenance do the gripper need?

Initially just more regular oil changes and then adjusting of the plates as they wear and the ramp rates change, and ultimately replacing them.

Not especially hard, but trouble is, its not like an F20 vauxhall box where in half an hour you can have the diff out on the driveway and back in!

 

[Harbinger]

^ was thinking exactly that Chip, going on the quotes here I had a mate get his Diff Fitted on a Cavalier for £90 after hours job @ Now VX Heathrow, these prices are mental.

 

[JackJack]

Thanks chip another question.

Is it true you can't use a roller brake tester with an lsd fitted? Remember someone telling me you can't.

 

[Cup_Phil]

That is true.

 

[Chip-mk1]

Thanks chip another question.

Is it true you can't use a roller brake tester with an lsd fitted? Remember someone telling me you can't.

You risk transmitting the load across the diff and hence wearing it / breaking it if you do, although for a quaiffe it appears to be fine IME.

 

[Chip-mk1]

^ was thinking exactly that Chip, going on the quotes here I had a mate get his Diff Fitted on a Cavalier for £90 after hours job @ Now VX Heathrow, these prices are mental.

The diff itself is much cheaper too because:
it doesnt have the enormous dimensions of the clio one (and they are NOT in a place that makes it strong, it just has to be cut from a big bit of metal)
The crown wheel on a vauxhall is bolt on

 

[Chip-mk1]

PS

And on that note, the fact that the mfactory diff is listed as not in stock anywhere and only about 30 quid difference to a vauxhall one, makes me wonder if they have ever even really made one, lol

 

[MG cup]

Brake testing a plated diff car just needs both rollers running at the same time, you do get some transmission wind up though. Going by your theory on brake testers for Quaife which is correct Chip proves that there not that great. They distribute torque to the wheel with most torque so are only ever one wheel drive.

All I'm saying is Phil, why spend 80% of a grippers value on a quiafe by chips maths when you could spend a few hundred more and have a proper diff.

 

[Cup_Phil]

PS

And on that note, the fact that the mfactory diff is listed as not in stock anywhere and only about 30 quid difference to a vauxhall one, makes me wonder if they have ever even really made one, lol

Yes - I know grinspeed have fitted a couple to track clios.
They're US made so no-one in the UK will stock them.

Brake testing a plated diff car just needs both rollers running at the same time, you do get some transmission wind up though. Going by your theory on brake testers for Quaife which is correct Chip proves that there not that great. They distribute torque to the wheel with most torque so are only ever one wheel drive.

All I'm saying is Phil, why spend 80% of a grippers value on a quiafe by chips maths when you could spend a few hundred more and have a proper diff.

Well yes initial outlay is £1200 or £1500 - but gripper will need re-torquing and re-plating eventually which makes me think the 2nd hand prices when I get bored of the clio in a few years would be lower as people will be worried about on-going maintenance. Whereas the £1200 for a quaiffe I've seen people sell the gearboxes for £1100 2nd hand.

I do agree with chip that the fit and forget you get with quaiffe combined with everyone know thing the name does end with high resale values.

I'm just not sure at the moment that the difference on my car between a full plate diff and the quaiffe diff would be noticeable by someone like me.

 

[Chip-mk1]

They distribute torque to the wheel with most torque

eh?

That just made no sense at all TBH, was the second torque supposed to be a different word?

so are only ever one wheel drive.

Totally incorrect, you seem to know nothing at all about the quaiffe or how it works TBH mate, what it is, is a torque biasing diff, and it does a pretty good job of distributing the torque between the two wheels so that whichever has the most grip gets sent the most power, to allow you to use all the grip available, the only exception to this is that in order to do so it needs at least a tiny bit of resistance on both wheels, without this it wont work which is why I have said if you have one wheel off the ground it wont work, but the rest of the time they work really well.

I assume you havent ever driven a clio with a quaiffe, as you seem to be spouting some real nonsense about them mate (which doesnt seem like you at all)

 

[Westyfield2]

In the Quaiffe scenario with the wheel up in the air spinning and no resistance... would ESP braking the wheel give it the tiny bit of resistance that the Quaiffe ATB needs to work? Just thinking out-loud, not that you'd normally have ESP enabled on track (or at all if you're a driving hero).

 

[Dan@SJM]

Doesn't the quaife multiply the torque of that with the least grip over to the wheel with the most grip?

I.e you have 25% traction on the left so it sends 75% of the torque over to the right?

 

[Chip-mk1]

In the Quaiffe scenario with the wheel up in the air spinning and no resistance... would ESP braking the wheel give it the tiny bit of resistance that the Quaiffe ATB needs to work? Just thinking out-loud, not that you'd normally have ESP enabled on track (or at all if you're a driving hero).

Surely ESP wouldnt be braking the wheel in the air though, as it would be going slower than the one on the track?

But in a non ESP/ABS car when you lightly apply the brake (ie if you are left foot braking into a corner) then yes that will actually help the diff work.

 

[Chip-mk1]

Doesn't the quaife multiply the torque of that with the least grip over to the wheel with the most grip?

I.e you have 25% traction on the left so it sends 75% of the torque over to the right?

Yes thats exactly what it attempts to do, but it effectively gets a "divide by zero" error when one wheel has no traction at all, lol.

 

[Dan@SJM]

Glad I got it right lol. Trying to rack my brains for something I was taught bloody years ago!

 

[MG cup]

eh?

That just made no sense at all TBH, was the second torque supposed to be a different word?




Totally incorrect, you seem to know nothing at all about the quaiffe or how it works TBH mate, what it is, is a torque biasing diff, and it does a pretty good job of distributing the torque between the two wheels so that whichever has the most grip gets sent the most power, to allow you to use all the grip available, the only exception to this is that in order to do so it needs at least a tiny bit of resistance on both wheels, without this it wont work which is why I have said if you have one wheel off the ground it wont work, but the rest of the time they work really well.

I assume you havent ever driven a clio with a quaiffe, as you seem to be spouting some real nonsense about them mate (which doesnt seem like you at all)

I'm on my phone with near dial up connection its an easy over site in 4" screen, you knew what I was trying to say which was grip.

I know exactly how the diff works, there a torque biassing diff (with straight helical gears instead of bevel) as I said and are constantly dividing the torque to the wheel with the most grip (if the wheels are well planted that is) and vary from anything from 0-100% from what I have actually read outside Quaifes sales bumph (check google if you dont want to believe me they dont work quite how they are portrayed and behave more like an open diff in a lot of situations)

They are great as I have said for high mileage road car as they are an improvement over an open diff in some situations.

And Chip no I haven't been in a Clio with a Quaife but that's irrelevant, they operate the same whichever casing their in or engine their attached to. CS has the servicing schedule down as a yearly thing which couldn't be further from the truth.

 

[Chip-mk1]

I'm on my phone with near dial up connection its an easy over site in 4" screen, you knew what I was trying to say which was grip.

I know exactly how the diff works

If you know how they work, then why say something as incorrect as they are "only ever 1 wheel drive"?

I am struggling to find a reason why you are posting the nonsense you are posting on this thread if you do have at least a vague clue how the diffs work?

there a torque biassing diff (with straight helical gears instead of bevel) as I said and are constantly dividing the torque to the wheel with the most grip (if the wheels are well planted that is) and vary from anything from 0-100% from what I have actually read outside Quaifes sales bumph (check google if you dont want to believe me they dont work quite how they are portrayed and behave more like an open diff in a lot of situations)

I currently own 3 cars with quaiffe diffs, I have owned many others in the past, and driven literally dozens, so I dont need to google how they work or where they dont quite manage to achieve what they are trying to, I am talking from a massive amount of first hand experience, including comparing them in multiple cases to a gripper diff in the same type of car on a variety of surfaces.

They are great as I have said for high mileage road car as they are an improvement over an open diff in some situations.

They are a huge improvement over an open diff in 99.99% of places when the standard diff has a problem, the exception being if you lift a wheel.

The gripper is a huge improvement during that 0.01% of the time, but is actually worse than the standard diff in other situations where the Quaiffe isnt.

So with the quaiffe you get most of the benefits of the gripper, but with none of the drawbacks (other than purchase cost)

And Chip no I haven't been in a Clio with a Quaife but that's irrelevant, they operate the same whichever casing their in or engine their attached to. CS has the servicing schedule down as a yearly thing which couldn't be further from the truth.

Well if you have been in ANY car with a quaiffe diff, you would realise your comments about them being barely any better than a standard diff were total nonsense surely?
Even at knockhill where you are apparnetly on 2 wheels a lot, the split second you touch down, till the moment you have enough grip that the standard diff no longer has an issue, the quaiffe would still give a big advantage over the standard diff, so if you are struggling with grip on the standard diff for 50 yards, and off the ground for 10 yards then 80% of the time the standard diff had a problem even in that very peculiar circumstance the quaiffe would still benefit you.


Its a huge improvement over standard, to say otherwise is to have no experience of them or knowledge of how they work!

 

[MG cup]

Chip stick to educating the CS masses, they will believe any old s**t you spout. Both diffs have there uses simple as, what you think falls into where is up to yourself. You clearly don't read my posts so on that note I'm out, had enough of Chipapedea for one day.

 

[NorthloopCup]

Chipapedea

Sorry but I lol'd out loud at this! Well done that man!

On a Quaife diff note though, I ran one in my turboed mk3 Astra coupled with a straight cut gearkit also from Quaife and I liked everything about how the Quaife put the power through to the front wheels. It wasn't just some s**t chipped let that it was coupled too either, it was a full on forged custom everything jobbie that had at one point in time 420hp @ 2bar of boost. Yes a gripper would've possibly put the power down better/earlier, but for me at that point in time the Quaife was awesome. I've never had any experience of a gripper so I can't and wouldn't pass comment on them. This is where chip's experience of both becomes invaluable for comparisons imo.

 

[Chip-mk1]

Chip stick to educating the CS masses, they will believe any old s**t you spout.

but its you doing that about the quaiffe mate? I'm stickin to talking accurately about them from firsthand experience.

Both diffs have there uses simple as[/quote]
Absolutely. If I was racing then as per my initial comments id go gripper.

what you think falls into where is up to yourself. You clearly don't read my posts so on that note I'm out, had enough of Chipapedea for one day.

I have read your posts, but if you think I'm saying quaiffe is always the answer you haven't read mine!
there are situations where the quaiffe is better and some where the gripper is. We both agree on that, what we disagree on is quaiffe being "only ever one wheel drive" in your opinion. I know that isn't even close to the case so of course I will disagree with it.