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Detroit Lockers


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#1 cedarsf1

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Posted 08 November 2018 - 07:13

Can anyone explain how a Detroit Locker operates? When does it lock up, and when is the diff open?

 

How do you drive a car with one of these--mainly how do you avoid the terrible understeer that is characteristic of this type of LSD?



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#2 Fat Boy

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Posted 08 November 2018 - 18:57

Honestly, do a bit of research for yourself. This is not a difficult thing to search.

 

1. It fully locks the wheels with across the axle when a certain drive torque is applied (regulated based on the internal spring).

2. It fully locks (like a spool) on throttle and acts as an open differential without drive torque (off-throttle).

 

To drive:

 

The main problem with a D.L. is the fact that it's completely open during braking and corner entry. This provides no yaw stability through the complete unlocking of the rear tires. There is no preload with a D.L. <<<<<This is wrong, I've fixed it later in the thread.

 

Detroit lockers are primarily used on tin-tops. These cars have relatively high C.G.'s. When cornering steady-state, the inside rear tires are very light and they don't provide a large understeering moment. The 'terrible understeer' is largely based on people who haven't actually worked with differentials. It does mean that when driving a car with a D.L. (or a spool), you need to be patient before applying throttle mid-corner and allow the car to rotate. When you go to throttle, the car is going to continue to turn, but less so than a car with an open differential. Honestly, this is the correct way to drive regardless of the differential. Most plate-style differentials act in a very similar manner. They're not nearly as variable or smooth as we often portray them. Generally speaking, at some low throttle input level (5-20% depending on setup) the rears lock solid in a relatively abrupt manner.

 

The place where you can run into problems is when you have on-throttle directional transitions (i.e. an 'S' section of a track). To get the car to transition, you may have to fully lift off the throttle to get the diff to disengage and allow the transition. The other option (and one more commonly used) is to just be more aggressive with the steering inputs and get the car a little loose to rotate. The tuning option that you have with a D.L. is the release spring. The stiffer the spring, the more difficult it is to make the differential unlock. The softer the spring, the easier it is to get the differential to unlock. In general, when you're driving a locked rear end on the car, you need to be patient enough to allow the car to rotate. When you go to throttle, you need to do be able to do it once and commit to it. Hopping on and off the throttle is not suffered gladly. If the car understeers, you need to lift, botch the corner and fix it the next lap by being more patient. If the car oversteers, stay on the gas and catch the slide.


Edited by Fat Boy, 20 November 2018 - 23:49.


#3 cedarsf1

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Posted 16 November 2018 - 12:56

Thanks for the detailed response!

You mentioned the release spring used for tuning the D.L. So you can tune how easily the unit locks and unlocks, correct? But once it's locked, it's 100% locked, unlike the operation of a Posi or a Torsen, correct?



#4 Greg Locock

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Posted 17 November 2018 - 00:07

Spot the deliberate error in this http://www.eaton.com...detroit-locker/



#5 NotAPineapple

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Posted 17 November 2018 - 11:57

Looking at the video it seems like a pretty pointless device. It appears to remain locked until you are already inside the corner (so corner entry US will be as if you have a spool), and then it disconnects the outer wheel and sends all the torque to the lighter loaded inner wheel which typically has <<10% of the tractive capability of the outer wheel.



#6 Greg Locock

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Posted 17 November 2018 - 23:51

Even the manufacturer can't describe how it works. When going straight ahead there is NOT an equal torque split between the wheels, as Mr Eaton claims.

 

"Operation

During straight-line driving, the Detroit Locker captures 100% of available torque and sends it equally to both wheels"

 

No, that's how an open diff works. In straight ahead a DL locks the two halfshafts together so they run at the same speed. It's hardly any wonder that the nuff-nuff and fanboi websites are so full of unreliable explanations when the manufacturer gets it wrong as well.



#7 Greg Locock

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Posted 20 November 2018 - 04:15

@FB, I've never had one to take apart, is there a ramp on the teeth of the dog clutches? If not what forces the dog clutch to disengage if the halfshaft is trying to rotate faster than the hypoid? The Eaton site seems pretty blase about the lubricant, I'd have thought that would affect the  unlocking speed-difference.


Edited by Greg Locock, 20 November 2018 - 04:22.


#8 Fat Boy

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Posted 20 November 2018 - 23:27

Spot the deliberate error in this http://www.eaton.com...detroit-locker/

 

And this "the internal components unlock to allow one wheel to spin faster or slower as necessary (free wheel)"

 

It really only allows one wheel to spin slower. The slower wheel will always be the inside and it's the other one that stays in constant contact with the engine.


Edited by Fat Boy, 21 November 2018 - 00:23.


#9 Fat Boy

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Posted 20 November 2018 - 23:30

Even the manufacturer can't describe how it works. When going straight ahead there is NOT an equal torque split between the wheels, as Mr Eaton claims.

 

"Operation

During straight-line driving, the Detroit Locker captures 100% of available torque and sends it equally to both wheels"

 

No, that's how an open diff works. In straight ahead a DL locks the two halfshafts together so they run at the same speed. It's hardly any wonder that the nuff-nuff and fanboi websites are so full of unreliable explanations when the manufacturer gets it wrong as well.

 

Yes, you either hold the speeds equal and allow a torque split(locked) or hold torque equal and allow a speed differential (open). A limited-slip differential, whether it be plate or gear derived friction, is the only that mixes the two.



#10 Fat Boy

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Posted 20 November 2018 - 23:41

@FB, I've never had one to take apart, is there a ramp on the teeth of the dog clutches? If not what forces the dog clutch to disengage if the halfshaft is trying to rotate faster than the hypoid? The Eaton site seems pretty blase about the lubricant, I'd have thought that would affect the  unlocking speed-difference.

 

The side springs force the driven dogs to engage the drive dogs in the center of the Detroit Locker. There is a small cam that pushes against the spring and will pop the faster rotating side free. The differential speed that it takes to pop the dogs free might be very slow. The differential torque that it takes to pop the dogs free will be a function of the side springs. The softer the spring, the easier it pops open. Incidentally, the level of differential torque which is necessary to compress the side spring and pop the differential open is analogous to preload on a clutch style differential.

 

The locking of a Detroit Locker is a mechanical interaction, not one that relies on friction. They are pretty damned tough. If the lubrication is good enough to take care of the CW&P, it'll be fine for the diff.



#11 Fat Boy

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Posted 20 November 2018 - 23:47

Looking at the video it seems like a pretty pointless device. It appears to remain locked until you are already inside the corner (so corner entry US will be as if you have a spool), and then it disconnects the outer wheel and sends all the torque to the lighter loaded inner wheel which typically has <<10% of the tractive capability of the outer wheel.

 

Read what I wrote about preload. It's similar to a plate-style diff. As far as sending the torque to the lighter loaded inner wheel, that's what all normal differentials do. A plate-style diff will have a torque bias ratio which is a multiplier. Whatever the lighter loaded side can support in terms of torque, the heavier loaded side will be able to support (bias ratio) x (lighter loaded torque). If it take 100 NM of torque to spin the inner tire and your diff has a 3.5 bias ratio, the outer tire will have 350 NM delivered to its side.


Edited by Fat Boy, 21 November 2018 - 00:25.


#12 Fat Boy

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Posted 21 November 2018 - 00:22


The main problem with a D.L. is the fact that it's completely open during braking and corner entry. This provides no yaw stability through the complete unlocking of the rear tires. There is no preload with a D.L. <<<<<This is wrong, I've fixed it later in the thread.

 

 

I had to reconsider what I wrote here, because it's wrong.

 

The side springs are forcing the dogs to engage and eliminates any side-to-side speed differential. This eliminates inside rear wheelspin because it is not able to 'overspeed'. If you get corner exit wheelspin with a D.L., it's always 2-wheel wheelspin.

 

Off-throttle on corner entry, the outside (faster) rear tire stays connected to the engine. Once a certain amount of differential movement happens between the two sides because of the inside rear _slowing_ (taking the shorter path/smaller radius around the corner). If you have very stiff side springs, there will never be enough differential tire rotation because this diff is all too happy to stay locked and drag the inside rear. This produces every bit as much understeer as a solid 'spool' drive. With a relatively soft side spring, the inside tire is not dragged along and the differential will pop open to allow the inside to slow down. At this point, the differential acts open. The torque differential necessary to produce the rotational differential across the axle is what we call preload on a limited-slip style differential. That's the point I was incorrect about. D.L.'s _do_ produce a preload which can be overcome with a certain torque split which produces differential motion.

 

With a plate-style differential, once the preload is overcome, the torque split will be a function the other internals and it's not necessary for any relative motion to occur. The D.L. requires a certain small amount of relative motion to lock. Once unlocked, it is completely unlocked whereas a plate style will never have less 'lock' than the preload and generally will have an additional coast lock which is a function of the engine overrun torque.

 

------------------------------------------------------------------------

 

We used to have a lot of conversations about these types of things. It's fun to think about them and really parse out what's happening. I *think* I've got it right this time...at the very least, it's closer to right!



#13 cedarsf1

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Posted 27 November 2018 - 10:26

So just to reiterate to make sure I understand all this correctly,

1) With a DL it's all or nothing--the diff is either locked or open, never any in between as in something like a Positration.

2) Going down a straight road, the diff is locked. Going into a corner, it will fully unlock. The DL will then fully lock while still in the corner if you get into the throttle again.

3) I'm still confused as to how much you can use the springs to "tune" the DL, i.e controlling how easily it unlocks when going into a corner, or how quickly it will lock based on how much throttle is applied. For example, can you tune it so that you need to use a lot of throttle during cornering to get it to lock, and allowing the diff to remain open when only light throttle is applied? Can you also tune it to easily and immediately unlock as soon as you enter a corner?

 

Thanks for the info so far. I actually did do a lot of Google searching, but as this thread demonstrates, there is a lot of confusion about DL's.



#14 Fat Boy

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Posted 04 December 2018 - 00:07

1. Correct. A good way to think of the actual locking mechanism is a key & keyway. With the key in place, there is no relative motion.

2. The DL locks & unlocks based on the angular motion difference across the axle. A Salisbury differential (plate or cone-type which may or may not have ramps) is not position sensitive. They are torque sensitive. A viscous differential depends on rotational speed across the axle.

 

The DL will unlock when off-throttle in a corner, specifically a tight one which causes a fair bit of angular motion side-to-side. It will lock while in the corner and that locking is (for our purposes) instantaneous. It's a very digital thing, so the important thing to remember when driving one is that it takes both patience and aggression. When allowing the car to get around the corner off-throttle, have patience. Let the car turn. If you hop on the gas too early you will produce sudden and excessive understeer. When the car has rolled far enough around the corner that you can apply throttle, then you need to do so aggressively. A DL isn't going to put up with a lot of on/off/on/off throttle inputs. If you try that you'll get into a nasty lock/unlock situation and Lord help you. The correct approach is wait until the car has rotated through the corner then roll a single time to full throttle. If you side-step the rear you need to stay in the gas and steer appropriately. It's a little hard on tires, but it's a better choice than the alternative.

 

3. From what I've seen, the tuning springs actually have a fair bit of influence on the tuning of a DL. Although I think most road-race cars would use a fairly light lock spring, I would caution you just a little about putting in the minimum. One good aspect of a locker is that it eliminates single wheel rear brake lock. Without a little bit of force holding everything together, you could get into that situation. You'll probably want the it locked during the initial 20-30% of the corner, which will provide stability. Then it pops open and you roll the corner. On the gas, the thing locks for about the last 20% of the corner to eliminate single wheel wheelspin.

 

These things are pretty crude devices. Don't expect it to really do what you want. It will loosely approximate what you want when tuned correctly, but it's a digital answer to an analog problem. They're cheap. They're reliable. They're also best used when mandated by the sanctioning body so that everyone has the same basic problems. If you're racing a DL against a 'real' differential, don't expect miracles.



#15 Fat Boy

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Posted 04 December 2018 - 00:09

Incidentally, what's the application?



#16 cedarsf1

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Posted 05 December 2018 - 18:17

Thanks for the info. The car is a tube-chassis Trans-Am.



#17 Fat Boy

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Posted 05 December 2018 - 23:26

Perfect application. You may find you run different locking springs at different types of tracks, but the good news is that there's damned little you can really do with the thing, so it's best to pay attention to other variables once this one is 'in the ball-park'. Changing the Watts-link pivot height (roll center) is a good way to adjust the influence of your diff without actually adjusting the diff itself. The biggest thing that has to get sorted is your driver's technique. He has to understand what the DL gives him and what it doesn't. It's got some pretty serious limitations, but, when driven correctly, It's not as horrible as some (ahem, Carroll Smith) might have you believe.



#18 cedarsf1

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Posted 07 December 2018 - 07:02

Perfect application. You may find you run different locking springs at different types of tracks, but the good news is that there's damned little you can really do with the thing, so it's best to pay attention to other variables once this one is 'in the ball-park'. Changing the Watts-link pivot height (roll center) is a good way to adjust the influence of your diff without actually adjusting the diff itself. The biggest thing that has to get sorted is your driver's technique. He has to understand what the DL gives him and what it doesn't. It's got some pretty serious limitations, but, when driven correctly, It's not as horrible as some (ahem, Carroll Smith) might have you believe.



#19 cedarsf1

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Posted 07 December 2018 - 07:02

Ok so what advice should I give the driver? Thanks

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#20 Fat Boy

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Posted 13 December 2018 - 23:41

Ok so what advice should I give the driver? Thanks

 

I've already written it above, but it boils down to this, don't apply throttle with understeer.



#21 Lee Nicolle

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Posted 14 December 2018 - 12:22

Clonk bang clunk with the back of the car walking all over the place. Followed by snap of an axle. 

Why anyone would ever use those dumb things is beyond me. I have raced a car with one, that broke 31 spline Ford axles. And raced against many where you could see the cars all over the place like a mad womans s*it.

 

The car with the 31 spline axles was changed to a spool and was far better to drive though we had to train the driver how to use something positive.

There is various types of LSDs that are quite good on the road but last about 5 min in a race application. And a spool on the street is dumb, even a good LSD will turn cars backwards on wet greasy roads. Though the opposite on race cars.

 

Been there tried that!!  Pukka open wheels which are a LOT lighter with far less roll centre do use them with some success, but are very maintenance intensive. Including ring and pinions and bearings as all that friction material ends up in the oil.

 

Some models of cars cannot be welded, some models with minispools do not get enough axle engagement so still break axles. Though if you know what you are doing most can be welded with no problems. NEVER weld the cast iron to the spider gears! Proper full spool is always the best. Not alloy or so called ultra light as the flex and blow the gears apart. And the alloy ones [and I have seen steel ones do it too] strip the splines in the spool.

 

Here in Oz V8 stupidcars initially tried LSD and ratchetting lockers. Now they all use spools. Simpler, more positive and far less maintenance.

 

And anybody that says they cannot drive with a spool should take up golf!!



#22 Lee Nicolle

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Posted 14 December 2018 - 12:32

Spot the deliberate error in this http://www.eaton.com...detroit-locker/

That whole article is bullshit. Detroits are horrid things in road cars as well. May have some application in hard driven 4wds. But for them diff locks are the way to go. My last 100 series Toyota had them and was magic. They are/ where a factory option. Though NOT so good to turn corners with the front one!! But climb up steep pinches like  a mountain goat and just ok on the sand. That ofcourse with the centre diff locked as well.

My current Landcruiser has only factory rear LSD which is ok but not so positive. Though works all the time not just occasionally. So a trade off.



#23 Fat Boy

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Posted 14 December 2018 - 21:21

Well, Lee, you use them when the rule book mandates it. That's an easy enough question to answer.

 

Having said that, the cars I work with all have some version of a Salisbury LSD. The early Daytona Prototypes just used the spider gears for spreading force (Emco diff), but most everything before and since then has used ramps (except for the occasional Quaiffe/Zexel). They're pretty damned reliable. I'd say if you're trying to make a roadcar diff work on track the first thing you'd do is make sure the plates are all just steel plates. You don't want any (usually organic but maybe kevlar based) friction material on the plates.

 

Lee is right about using a spool. Especially in a sedan, you can make them work around a track. They're light, reliable and reduce confusion. They're also a nightmare in the wet.

 

DL's aren't anything special, but there are aspects of them that suck less than both spools or opens.

 

I used to do a little work with the Weismann folks. I always wanted them to build me one of their lockers, but I never could get anyone to pay for it!



#24 Lee Nicolle

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Posted 03 January 2019 - 23:24

Having raced with a spool in wet conditions I know what I would prefer. And it is NOT a detroit! A good LSD would possibly be the best but still only good for a few laps. High horsepower and wide tyres simply kill LSDs.

There is other styles I have not used or frankly wish too. May be ok in small engine open wheelers but not is a big sedan which is where all my experience comes from. Though on dirt, bitumen in all conditions.



#25 Fat Boy

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Posted 09 January 2019 - 18:10

Grumble, Grumble, Lee, LOL!

 

A D.L. is nothing special. I'll agree with you there. Pushing a car with a spool around the paddock should cure you of ever really *wanting* to run one.

 

I think your view of a plate-style LSD is possibly skewed by using street car parts in racing situations. I'm running one at the end of the month for 24 hours on a car with plenty of power, downforce and tire. Of the many, many things I'm worried about, it's low on the list. It'll lose 5 Nm of preload in it's first session or 2. It'll lose another 5 Nm over the race. Modern racing equipment is produced by staggeringly good companies. They're expensive as hell, but they work amazingly well.



#26 Greg Locock

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Posted 09 January 2019 - 21:14

Production car LSDs are nothing like race car ones. I'd estimate (ahem) one could burn some of them into complete uselessness with two tanks of fuel. On public roads.



#27 gruntguru

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Posted 09 January 2019 - 22:12

Any particular public roads?  :rotfl:



#28 Greg Locock

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Posted 10 January 2019 - 09:27

Two decades ago you could hoon around the back of the Otways all day, if you paid attention to logging trucks and milk trucks. We've got rid of the dairy industry, but substituted a million middle aged men in lycra, and of course more effective speed cameras and so on. So now I'm that tedious guy who drives exactly 2 kph over the speed limit (checked with gps) 90% of the time.



#29 Fat Boy

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Posted 12 January 2019 - 21:49

Production car LSDs are nothing like race car ones. I'd estimate (ahem) one could burn some of them into complete uselessness with two tanks of fuel. On public roads.

 

That's why I said you have to get the organic (usually) friction material off the plates. Racing diffs use hardened steel plates which probably have a somewhat lower mu and are definitely noisier at parking lot speeds, but they wear much better. Also, good racing diffs have some sort of preload spring in the mix, generally a large belleville washer, that maintains a consistent side pressure on the plates as they wear. Most street car diffs ignore this very important design point. In the end, a GM Posi or Ford Traction-Lok is no substitute for a real differential and it shouldn't be any real surprise if they perform poorly in a racing application.



#30 Fat Boy

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Posted 12 January 2019 - 21:50

Two decades ago you could hoon around the back of the Otways all day, if you paid attention to logging trucks and milk trucks. We've got rid of the dairy industry, but substituted a million middle aged men in lycra, and of course more effective speed cameras and so on. So now I'm that tedious guy who drives exactly 2 kph over the speed limit (checked with gps) 90% of the time.

 

Desmo is right here, Greg, you don't need to act like he won't read this!



#31 kikiturbo2

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Posted 15 January 2019 - 06:39

Production car LSDs are nothing like race car ones. I'd estimate (ahem) one could burn some of them into complete uselessness with two tanks of fuel. On public roads.

 

most production LSDs I see these days are either helical/torsen or some sort of active variety, usually plate with hydraulic pressure applied for locking. Normal plate diffs in road applications usually dont have, or have minimal preload... Hell, I have seen stock plate diffs with wrongly stacked plates, to provide less locking..



#32 Fat Boy

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Posted 15 January 2019 - 17:13

most production LSDs I see these days are either helical/torsen or some sort of active variety, usually plate with hydraulic pressure applied for locking. Normal plate diffs in road applications usually dont have, or have minimal preload... Hell, I have seen stock plate diffs with wrongly stacked plates, to provide less locking..

 

Yep. The helical gear diffs are simple, quiet, reliable and act more like an open in mixed-mu situations, so they are common. Most street cars don't have preload because they can be noisy in parking lots. It too bad, because preload has a bigger influence on handling than any other diff variable.

 

The plates don't *have* to be stacked drive/driven/drive/driven/etc. More lock is not always better. Varying friction faces is a good tuning method.



#33 Lee Nicolle

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Posted 19 January 2019 - 08:02

Grumble, Grumble, Lee, LOL!

 

A D.L. is nothing special. I'll agree with you there. Pushing a car with a spool around the paddock should cure you of ever really *wanting* to run one.

 

I think your view of a plate-style LSD is possibly skewed by using street car parts in racing situations. I'm running one at the end of the month for 24 hours on a car with plenty of power, downforce and tire. Of the many, many things I'm worried about, it's low on the list. It'll lose 5 Nm of preload in it's first session or 2. It'll lose another 5 Nm over the race. Modern racing equipment is produced by staggeringly good companies. They're expensive as hell, but they work amazingly well.

I will stick with a spool. Pushing them is not too bad unless the car has 10" of stagger! And the car has an engine, you drive it!

And 10" or so of stagger makes them turn really well!

And locked diffs are as in most applications cheap as a few feet of mig wire. I have been lucky in not breaking one since the 70s and have never used a full spool. Stronger, lighter and better all way around but in 50 years have never broken one since I learned to weld them properly. With a stick welder but mig is much cleaner, just keep blowing air through them when welding to limit the heat.

Vanguards, Zephyr, Holdens 6 diffs by the dozen, Holden 10 bolts, Austin A90s, early Commodore are all suitable to weld. 

9" Ford and Borg Warner diffs are not. You can but they will break. These days mini spools are so cheap as for those diffs never to bother though the Saloon Cars had a period of stripping the splines out as I guess they were wrong material or not heat treated properly. I have heard of that with drag racers too using alloy spools. Though that is not very surprising!!



#34 Fat Boy

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Posted 21 January 2019 - 00:23

Lee,

 

One thing I will say for the spool is, at the very least, it's consistent. In a saloon/GT car that has a (relatively) high C.G. and enough HP to have wheelspin as an issue, you could do a hell of a lot worse. I consistently preach about entry stability and you'd be hard pressed have any more stability than what you get out of a spool. I've never found mid-corner understeer to be that big of a deal as long as you have the chassis tuned appropriately. The biggest downside I have with a solidly locked rear is on power. When you do get wheelspin, it's always of the 2-wheeled variety. The rear tires lateral capacity goes from something to nothing very quickly. This often makes for drifitng, opposite lock and a possible tank-slapper (for the timid who lift).

 

Your point about reliability and cost doesn't fall on deaf ears, either. :up:



#35 kikiturbo2

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Posted 21 January 2019 - 08:53

There is an interesting video on porsche 962 by chris harris, and in it the cars constructor said that it used a spool, because it was the fastest solution for the platform.. .



#36 MatsNorway

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Posted 28 January 2019 - 07:37

Detroit locker sounds like something that might be handy on a front wheel driven car if anything.


Edited by MatsNorway, 28 January 2019 - 07:39.


#37 Greg Locock

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Posted 28 January 2019 - 12:07

100% frightening scenario i think. Which might be an improvement on some 150% frightening torque steer cars i've driven.



#38 MatsNorway

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Posted 30 January 2019 - 11:07

The trick is to give it more throttle when you get oversteer. :clap:

 

I actually have a video where you clearly can see the importance of correct gear and having some power ready to help you out in a sticky situation. First part is fourth gear, second is third.

Note: no servo, no ABS/assistance of any kind and no gloves and no support in seat at all so you have to support yourself by having the knee in the door++ Which is why it is so hard to downshift going into that corner.

If i had my knee straight when i initiate heel and toe i would hit the wheel with the knee.

https://www.youtube....h?v=-GocPUZPL4A

 

More serious: Would a Detroit locker be so bad tho? It is open on corner entry but would give a lot more mid to exit corner steering.

 

I guess the stabilizing effect from hitting the gas in a normal car is that the power is transferred to the inner wheel. Thus trying to rotate the mass in the opposite direction of the corner thus inducing understeer.

 

But by loading the outer front you nullify that effect, in turn you get only the extra rear grip from the stronger weight transfer. Not allways ideal. I guess it would be scarier in some situations on corner entry oversteer where you normally would throttle out of it.


Edited by MatsNorway, 30 January 2019 - 11:31.


#39 Fat Boy

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Posted 01 February 2019 - 22:47

1. Mats, reread my description. You've misunderstood how they work.

2. They'd suck in a FWD car because of the severity in how they lock/unlock. It'd likely pull the wheel out of your hands.

3. That driving video was just bloody awful. If you're going to post something like that, be prepared to have the piss taken.



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#40 Fat Boy

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Posted 01 February 2019 - 22:54

There is an interesting video on porsche 962 by chris harris, and in it the cars constructor said that it used a spool, because it was the fastest solution for the platform.. .

 

Keep in mind a couple things.

 

1. Differentials have improved significantly over the last 35 years or so.

2. A 962 was an endurance car. A big part of winning an endurance race (especially then) is surviving. In a time where $$$ and technology was limited, this was a good way to improve reliability. Harris may *think* a spool was the fastest solution, but if that's the case, I think you'd see more spools in present day pro racing. You only see them on ovals (w/ tire stagger) and where mandated.



#41 Canuck

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Posted 02 February 2019 - 19:21

To be fair to Kiki (and Chris), the post says the car constructor claimed it was fastest solution (which as you point out does not necessary mean fastest period, but fastest of the compromises).

#42 Fat Boy

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Posted 04 February 2019 - 02:05

To be fair to Kiki (and Chris), the post says the car constructor claimed it was fastest solution (which as you point out does not necessary mean fastest period, but fastest of the compromises).

 

In all fairness, has any German car constructor ever said anything other than their answer to a given problem was the best?



#43 kikiturbo2

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Posted 04 February 2019 - 10:10

actually they said it was fastest "at that time".... i.e. with then available differential and tire tech.. .and they did try a normal ZF diff too.. These days the would use a active diff of some sort and be done with it..
 

 

The point about surviving is of course a valid one, simplicity if often the best solution.... It took drifters way too long to accept a spool in their cars.. :D



#44 Canuck

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Posted 04 February 2019 - 13:39

In all fairness, has any German car constructor ever said anything other than their answer to a given problem was the best?

Sorry, I wasn’t clear. You said “Harris might think...”. I was suggesting that Harris is only the personality presenting things, not the constructor. Unless the constructor is also named Harris, he didn’t claim it was the fastest, the constructor did. [/pedant]

#45 Fat Boy

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Posted 04 February 2019 - 16:36

Sorry, I wasn’t clear. You said “Harris might think...”. I was suggesting that Harris is only the personality presenting things, not the constructor. Unless the constructor is also named Harris, he didn’t claim it was the fastest, the constructor did. [/pedant]

 

I knew what you were getting at. My second comment was slagging Porsche a bit. Whether it was or not, if Porsche said it was the fastest, they're prone to making damn sure it will be the fastest (even if it needs engine remapping or a set of Q tires to make it so).



#46 kikiturbo2

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Posted 05 February 2019 - 08:48

 

The championships won by teams campaigning the 962 included the World Sportscar Championship title in 1985 and 1986, the IMSA GT Championship every year from 1985 to 1988, the Interserie championship from 1987 until 1992, all four years of the Supercup series (1986 to 1989), and the All Japan Sports Prototype Championship from 1985 until 1989, and it was also very dominant in the American IMSA series well into the 90's. The 962 also won the 24 Hours of Le Mans in 1986 and 1987, with Derek Bell, Al Holbert and Hans-Joachim Stuck at the wheel on both occasions, as well as later winning under the Dauer 962 badge in 1994.

The presence of strong factory teams, such as Jaguar, Mercedes-Benz, Nissan, and Toyota, competing against privateer 962s eventually led to the car becoming less successful in the later 1980s. Even though they struggled, 962s would continue to win races into 1993, taking lone victories in the IMSA GT and Interserie seasons. Although Dauer's Le Mans victory in 1994 featured a highly modified car, Team Taisan would take the final victory ever in an original 962C, winning an All Japan Grand Touring Car Championship event at Fuji Speedway in August of that year, just over ten years after the car had debuted.

 

I would say that mr Singer was obviously right.. :D



#47 MatsNorway

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Posted 06 February 2019 - 18:09

3. That driving video was just bloody awful. If you're going to post something like that, be prepared to have the piss taken.

 

That was my second or third time ever on a track. You where not even specific about anything.

 

https://youtu.be/dsOrDCeVXRo?t=98

Evaluate this then.

 

Can you see something strange about the handling of car? Surely you of all should be able to tell what is going on.. 


Edited by MatsNorway, 06 February 2019 - 18:13.


#48 kikiturbo2

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Posted 06 February 2019 - 22:33

you have massive understeer... change the driving style



#49 gruntguru

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Posted 06 February 2019 - 23:57

Scandinavian flick?  :lol:  



#50 Kelpiecross

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Posted 07 February 2019 - 04:02

I presume that it is a front wheel drive car? It looked pretty good to me - very stable and predictable - as a FWD should be. Maybe a little more air in the front tyres?

Edited by Kelpiecross, 07 February 2019 - 04:03.