Sam Overton on a number of threads has mentioned building Anti squat geometry into the rear suspension of various rigs.and Ben aka Isuzurover has mentioned it on another thread. I would guess that many out there do not really know what that means, so although I am no expert on the subject i will try to explain what I know and maybe others who have a better understanding can correct me, or share their knowledge.
When a truck is climbing a steep gradient, weight transfer tends to unload the front axle and load up the rear one, which is not a desirable situation.
if you have a high degree of antisquat geometry in your rear suspension linkage, you can conteract the effect of weight transfer.
The rear radius arms on a series 2 Discovery or a Merc Gwagon are a good example to explain antisquat dynamics.
When you apply torque to the rear diff the reaction is to rotate the axle housing in the opposite direction to that of the ringgear. because the radius arms are secured to the axle housing, this force tries to swing the forward end of the radius arm upwards, and because the forward end of these radius arms are attached to the trucks chassis, this force imparts a lifting effect at the chassis attachment point. This is antisquat.
The degree of anti squat is determined by the overall length of the radius arms. Eg long arms= left lifting force. Short arms= more lifting force.
I could waffle on a lot more about antidive and squatting under deceleration etc, etc. but I am interested in reading the opinions of others before I do so .
Regards Bill
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Anti Squat, anti Dive suspension geometry.
Moderator: Micka
Bill, I don't know if you have browsed over at PirateBB, but is has been discussed well past the point of the corpse decomposing....
This guy has built a nice spreadsheet for doing the calcs
There is this really long discussion
And this one
Just to point out a few quick ones. You'll need the hip waders to get through the BS, but there is some real information hidden over there.
This guy has built a nice spreadsheet for doing the calcs
There is this really long discussion
And this one
Just to point out a few quick ones. You'll need the hip waders to get through the BS, but there is some real information hidden over there.
The weight transfer is due to acceleration. The forces can be resolved into a single equivalent force acting through the centre of gravity and has a direction opposite to the direction of acceleration.
To comply with the laws of equilibrium, with forward acceleration, weight appear to be transferred from the front to rear wheels. This would normally compress the rear springs (squat). With rear link suspension, traction force (between tyre and ground) is transferred through the links to the chassis. The lower link is in compression and the upper links in tension. Now, if the lowers links are angled upward from the axle to the chassis, the compression force has a horizontal component (the traction force) and a vertical upward component ( the traction force times sine of the angle of the link to the ground). For equilibrium the vertical forces at the rear (weight distribution plus weight transfer) is carried by springs plus the vertical components of the link forces.
Anti squat is forces in links countering squat. For 100% antisquat the vertical resultant of the link forces is exactly opposite to the weight transfer and the rear will not squat. Antisquat can exceed 100% and in this case the rear of the vehicle will rise during acceleration.
Antidive is similar - acceleration is in the reverse direction, so weight appears to transfer to the front causing dive.
To comply with the laws of equilibrium, with forward acceleration, weight appear to be transferred from the front to rear wheels. This would normally compress the rear springs (squat). With rear link suspension, traction force (between tyre and ground) is transferred through the links to the chassis. The lower link is in compression and the upper links in tension. Now, if the lowers links are angled upward from the axle to the chassis, the compression force has a horizontal component (the traction force) and a vertical upward component ( the traction force times sine of the angle of the link to the ground). For equilibrium the vertical forces at the rear (weight distribution plus weight transfer) is carried by springs plus the vertical components of the link forces.
Anti squat is forces in links countering squat. For 100% antisquat the vertical resultant of the link forces is exactly opposite to the weight transfer and the rear will not squat. Antisquat can exceed 100% and in this case the rear of the vehicle will rise during acceleration.
Antidive is similar - acceleration is in the reverse direction, so weight appears to transfer to the front causing dive.
John
Yeah red 90, your right about the waders! I think I will pass and see what response we get on this forum. I deliberately posted this thread on the rover forum because I believe Rover folk to be generally more able to hold a discussion without it degenerating into a mudslinging bullshit contest.
Regards Bill.
Regards Bill.
I'll describe it as best as I understand it.... One day I'll read suspension design book....
OK, well looking at the drawing above. The point where the projections of the links meet is the "instantaneous center" (IS). In other words the point about which the axle is rotating at that part of the suspension movement. In a radius arm design, it would be the pivot point.
When accelerating, the forces from the rear tyres act through the center of gravity. The pivot point is the front suspension, so the line of neutral squat (no antisquat or squat) is drawn from the rear tyre through a point inline with the front axle at the height of the center of gravity as shown. This is called the "asntisquat line" (AS)
If the IS is above the AS line, you get antiquat (rear end lifts under power). If below, you get squat
Now one thing I've never really thought about is affect of being on a hill. I guess, the AS line would drop, effectively increasing the antisquat.
The reasoning for wanting some AS on a 4WD is that when power is applied, the rear tyres push down somewhat aiding in traction. But there are ways of making it go unstable, so you really need to look at all the cases and be careful.
OK, well looking at the drawing above. The point where the projections of the links meet is the "instantaneous center" (IS). In other words the point about which the axle is rotating at that part of the suspension movement. In a radius arm design, it would be the pivot point.
When accelerating, the forces from the rear tyres act through the center of gravity. The pivot point is the front suspension, so the line of neutral squat (no antisquat or squat) is drawn from the rear tyre through a point inline with the front axle at the height of the center of gravity as shown. This is called the "asntisquat line" (AS)
If the IS is above the AS line, you get antiquat (rear end lifts under power). If below, you get squat
Now one thing I've never really thought about is affect of being on a hill. I guess, the AS line would drop, effectively increasing the antisquat.
The reasoning for wanting some AS on a 4WD is that when power is applied, the rear tyres push down somewhat aiding in traction. But there are ways of making it go unstable, so you really need to look at all the cases and be careful.
Red90, I can only see the small pictures and they are not clear enough for me to refer to, so I apologise if I have interpreted your words incorrectly.
The line from ground at rear tyre to heght of C of G at front axle is the line of 100% antisquat (for a rigid axle but not for IRS).
If the instant centre is below this line antisquat will be less than 100%, but it is still antisquat if it is greater than 0%. 80% antisquat is generally accepted as a good compromise (height to IC is 80% of the height to the 100% antisquat line at that position).
The line from ground at rear tyre to heght of C of G at front axle is the line of 100% antisquat (for a rigid axle but not for IRS).
If the instant centre is below this line antisquat will be less than 100%, but it is still antisquat if it is greater than 0%. 80% antisquat is generally accepted as a good compromise (height to IC is 80% of the height to the 100% antisquat line at that position).
John
Used to play with this stuff on race cars. A lot.
You've all got it sussed.
It can be used to very good effect to control pitch, particularly when you have a lot of grunt and very soft springs. Sam's Rock buggy springs to mind. However, and there is always a however, 'cause everything is a compromise....
The biggest problem with anti anything suspension geometry is that it can take a hell of a lot of compliance out of the suspension. The more 'anti' the less compliance. The suspension links end up 'fighting' each other.
It can get, as Bush65 wrote, to the point where the suspension binds, or the chassis moves the 'wrong' way.
For example, I really don't want to introduce any more anti-squat on the rear of my crew cab as the springs I'm running are so bloody stiff (it's a work truck) and it's so under powered that it would work against me off road and just bind things up.
If I had a buggy that weighed bugger all, with 300 HP and super soft, long springs, and that would lift its nose skyward whenever I breathed on the throttle, well I'd be dialling in some anti-squat.
If it had a multi link front end I might look at dialling in anti-lift there so that I didn't compromise traction on the rear.
Of course, the downside of too much anti-squat means that it accentuates lift, and this could be sphincter puckering going down a steep hill, as it would encourage the rear suspension to lift the chassis skyward.
We used to reduce the pitch on open wheeler race cars by dialling in nil or zero droop in the front and rear ends.
With the lateral load transfer under power, as the rear squats the front lifts around the C of G, taking load off the front tyres. This would induce mid corner understeer, and scrub off stacks of speed. A crude and effective fix is to limit the droop of the front suspension to normal ride height, (ie: the wheels don't drop when the chassis is lifted) effectively reducing the lateral load transfer, keeping the weight on the front wheels (in reality, only unsprung weight) and curing the understeer. It also artificially reduces the amount of roll (but not the roll centre, this is something different entirely). Restricting the rear droop obviously stopped the rear of the car lifting as much under brakes, enabling the driver to get more effective braking from the rear tyres. The downside of this was the unloading of the inside rear wheel when cornering, a disaster in cars that weren't allowed limited slip diffs. One particular car was adorned with a very crafty rocker between the suspension rockers to enable roll while limiting droop.
If we used anti-lift, the trade off (there is always a trade off) would have been excessive dive under brakes with the relatively soft spring rates we were using (Formula Fords). The best compromise was nil droop. Worked great on smooth bitumen, not very effective over ripple strips that wouldn't trouble a Honda Civic.
A couple of seasons ago Ferrari were running anti-lift in the front end (those cars are unbelievably sensitive to ride height variations aerodynamically) but the potential increase in dive was offset by running a third spring/damper system for pitch control.
Whats all this race car bullshit got to do with Land Rover's ?
They are both trying to do the same thing and keep all four wheels on the ground to gain the maximum amount of grip. The physics are the same.
How much anti is the right amount ? only testing can tell. It's a bit like some of my old pommy suspension books, filled with all the theory and tons and tons of equations.
Great for selecting a base line, but once you've done that, its all academic. Just adjust with more or less, till the vehicle feels/works best.
Cheers,
Rick.
You've all got it sussed.
It can be used to very good effect to control pitch, particularly when you have a lot of grunt and very soft springs. Sam's Rock buggy springs to mind. However, and there is always a however, 'cause everything is a compromise....
The biggest problem with anti anything suspension geometry is that it can take a hell of a lot of compliance out of the suspension. The more 'anti' the less compliance. The suspension links end up 'fighting' each other.
It can get, as Bush65 wrote, to the point where the suspension binds, or the chassis moves the 'wrong' way.
For example, I really don't want to introduce any more anti-squat on the rear of my crew cab as the springs I'm running are so bloody stiff (it's a work truck) and it's so under powered that it would work against me off road and just bind things up.
If I had a buggy that weighed bugger all, with 300 HP and super soft, long springs, and that would lift its nose skyward whenever I breathed on the throttle, well I'd be dialling in some anti-squat.
If it had a multi link front end I might look at dialling in anti-lift there so that I didn't compromise traction on the rear.
Of course, the downside of too much anti-squat means that it accentuates lift, and this could be sphincter puckering going down a steep hill, as it would encourage the rear suspension to lift the chassis skyward.
We used to reduce the pitch on open wheeler race cars by dialling in nil or zero droop in the front and rear ends.
With the lateral load transfer under power, as the rear squats the front lifts around the C of G, taking load off the front tyres. This would induce mid corner understeer, and scrub off stacks of speed. A crude and effective fix is to limit the droop of the front suspension to normal ride height, (ie: the wheels don't drop when the chassis is lifted) effectively reducing the lateral load transfer, keeping the weight on the front wheels (in reality, only unsprung weight) and curing the understeer. It also artificially reduces the amount of roll (but not the roll centre, this is something different entirely). Restricting the rear droop obviously stopped the rear of the car lifting as much under brakes, enabling the driver to get more effective braking from the rear tyres. The downside of this was the unloading of the inside rear wheel when cornering, a disaster in cars that weren't allowed limited slip diffs. One particular car was adorned with a very crafty rocker between the suspension rockers to enable roll while limiting droop.
If we used anti-lift, the trade off (there is always a trade off) would have been excessive dive under brakes with the relatively soft spring rates we were using (Formula Fords). The best compromise was nil droop. Worked great on smooth bitumen, not very effective over ripple strips that wouldn't trouble a Honda Civic.
A couple of seasons ago Ferrari were running anti-lift in the front end (those cars are unbelievably sensitive to ride height variations aerodynamically) but the potential increase in dive was offset by running a third spring/damper system for pitch control.
Whats all this race car bullshit got to do with Land Rover's ?
They are both trying to do the same thing and keep all four wheels on the ground to gain the maximum amount of grip. The physics are the same.
How much anti is the right amount ? only testing can tell. It's a bit like some of my old pommy suspension books, filled with all the theory and tons and tons of equations.
Great for selecting a base line, but once you've done that, its all academic. Just adjust with more or less, till the vehicle feels/works best.
Cheers,
Rick.
300Tdi Defender 130 CC
Bush65 wrote:If the instant centre is below this line antisquat will be less than 100%, but it is still antisquat if it is greater than 0%. 80% antisquat is generally accepted as a good compromise (height to IC is 80% of the height to the 100% antisquat line at that position).
Hmmm, that is not how I understand it. As I understand it, less than 100%AS gives squat. Greater than 100% gives lift in teh rear (antisquat). read the link below. 100% is the point where there is no suspension movement with acceleration. I think the confusion is that the term "antiquat" is meant to refer to the forces that resist "squat". When you have reached 100%, the antisquat forces exactly resist the squatting forces.....
Read this link, it explain the details
Hehe, I just noticed that the link is from a Mechanical & Space Systems Design course at the University of Queensland. How appropriate.....
As I understand it, less than 100%AS gives squat. Greater than 100% gives lift in the rear (antisquat). read the link below. 100% is the point where there is no suspension movement with acceleration. I think the confusion is that the term "antiquat" is meant to refer to the forces that resist "squat". When you have reached 100%, the antisquat forces exactly resist the squatting forces.....
John, while it (squat) may not be eliminated at % below 100% it is still termed anti-squat in general usage (every race car engineer I ever worked with termed it this way) and every suspension book I've ever picked up terms it this way, as it still limits the % amount of squat.
Smaller % definately do limit the effect of the lateral load transfer, and can be felt.
Rick.
300Tdi Defender 130 CC
Hi all
I think I am starting to understand all this AS, jacking, anti-dive etc. and how to go about putting together a 4 link suspension on a normal axle. However, I would like to know what influence portal reducing hubs have on locating the links and does one use the same methods for calculating AS % etc.
Any advise appreciated
I think I am starting to understand all this AS, jacking, anti-dive etc. and how to go about putting together a 4 link suspension on a normal axle. However, I would like to know what influence portal reducing hubs have on locating the links and does one use the same methods for calculating AS % etc.
Any advise appreciated
MikeMac wrote:Hi all
I think I am starting to understand all this AS, jacking, anti-dive etc. and how to go about putting together a 4 link suspension on a normal axle. However, I would like to know what influence portal reducing hubs have on locating the links and does one use the same methods for calculating AS % etc.
Any advise appreciated
Portal hubs don't affect the graphical method of determining the ant-squat. The loads in the links will be affected by the extra height from ground at the axle end of the links. Increasing the vertical separation between upper and lower links will go some way to reducing the link loads.
John
I remember years ago watching the Austin 7 club or Rover Scouts cross country trials. These were 2wd specials and some were built with extreme anti squat linkage geometry so that they could deliberately make the cars back end hop up and down for certain conditions.
In my opinion a high degree of anti squat should not be detrimental when descending steep gradients because under engine braking or service braking the tendency is for the rear diff housing to twist forwards which would try to pull the back of the chassis down via the radius rods. the front axle would also twist forward which would impart a lifting force via the radius rods to the front of the chassis. This seems like a desirable situation to me.
Bill.
In my opinion a high degree of anti squat should not be detrimental when descending steep gradients because under engine braking or service braking the tendency is for the rear diff housing to twist forwards which would try to pull the back of the chassis down via the radius rods. the front axle would also twist forward which would impart a lifting force via the radius rods to the front of the chassis. This seems like a desirable situation to me.
Bill.
i only just found this thread
Nissan, Suzuki, R,Rover, and Peerless Driver
there is some great stuff in it. one thing i did find interesting is that nobody touched on the fact that suspension geometry is constantly changing.
when a vehicle (doesn't matter if it an F1 or a monster truck) is exposed to an external force the dynamics of the vehicle change. all the reference to anti squat, roll axis, CoG. are made in a static state. which can only tell you how the vehicle will behave in a static state, ie. (stationary, it doesn't matter what’s going on when the vehicle is parked), (or moving at a constant velocity, which can never happen).
so unless you set out to simulate the suspension through its cycles, you really only have a very small part of an extremely large and complex picture.
i love this it is so true.
Stu
Nissan, Suzuki, R,Rover, and Peerless Driver
there is some great stuff in it. one thing i did find interesting is that nobody touched on the fact that suspension geometry is constantly changing.
when a vehicle (doesn't matter if it an F1 or a monster truck) is exposed to an external force the dynamics of the vehicle change. all the reference to anti squat, roll axis, CoG. are made in a static state. which can only tell you how the vehicle will behave in a static state, ie. (stationary, it doesn't matter what’s going on when the vehicle is parked), (or moving at a constant velocity, which can never happen).
so unless you set out to simulate the suspension through its cycles, you really only have a very small part of an extremely large and complex picture.
i love this it is so true.
rick130 wrote:How much anti is the right amount ? only testing can tell. It's a bit like some of my old pommy suspension books, filled with all the theory and tons and tons of equations.
Great for selecting a base line, but once you've done that, its all academic. Just adjust with more or less, till the vehicle feels/works best.
Cheers,
Rick.
Stu
[quote="COOP"] By the way Mr engineering Guru maybe you better get another calculator or learn how to use it![/quote]
www.indurooffroad.com
44mm and 38mm Roll Cage Tube
Eibach Springs SAW Shocks
www.indurooffroad.com
44mm and 38mm Roll Cage Tube
Eibach Springs SAW Shocks
Yep, I can vouch for Red90 there. This forum tends to eat diagrams and pictures. Hungry little bugger.
Almost any decent modern suspension program gives you data through a range of motion, usually in 3D.
Back when I was toally computer illiterate, (not much better now
) I used to do everything half scale with a board and string (there would be cotton stretched across the longe room floor) through all ranges for camber change, roll centre height and change, anti dive/squat, etc.
Rick.
Almost any decent modern suspension program gives you data through a range of motion, usually in 3D.
Back when I was toally computer illiterate, (not much better now
) I used to do everything half scale with a board and string (there would be cotton stretched across the longe room floor) through all ranges for camber change, roll centre height and change, anti dive/squat, etc.
Rick.
300Tdi Defender 130 CC
sorry guys i missed the drawings.
i do multipule layouts in 3D on auto cad and mechanical desktop.
i still do the calcs manually, which can be time consuming
to see reactions, i make up a 1:1 mock up out of small ERW and 1/4 rod ends.
Stu
i do multipule layouts in 3D on auto cad and mechanical desktop.
i still do the calcs manually, which can be time consuming
to see reactions, i make up a 1:1 mock up out of small ERW and 1/4 rod ends.
Stu
[quote="COOP"] By the way Mr engineering Guru maybe you better get another calculator or learn how to use it![/quote]
www.indurooffroad.com
44mm and 38mm Roll Cage Tube
Eibach Springs SAW Shocks
www.indurooffroad.com
44mm and 38mm Roll Cage Tube
Eibach Springs SAW Shocks
Whats needed now is for Rick or Stu to draw up a suspension system that will provide an extraordinary degree of axle articulation together with a high roll centre for side slope/compond slope stability.
I think if Lotuses Colin Chapman was interested in offroading he would have looked at it. Regards Bill.
I think if Lotuses Colin Chapman was interested in offroading he would have looked at it. Regards Bill.
bill
i can't go giving away all my secrets
but i have just finished a 4link (satchell link) for the rear of my patrol, and will be testing it out in the next few weeks once everything else is finished.
Stu
i can't go giving away all my secrets
but i have just finished a 4link (satchell link) for the rear of my patrol, and will be testing it out in the next few weeks once everything else is finished.
Stu
[quote="COOP"] By the way Mr engineering Guru maybe you better get another calculator or learn how to use it![/quote]
www.indurooffroad.com
44mm and 38mm Roll Cage Tube
Eibach Springs SAW Shocks
www.indurooffroad.com
44mm and 38mm Roll Cage Tube
Eibach Springs SAW Shocks
Turning the clock back 80 years or more, I'd be interested to know Ricks, Stu's or anyone elses opinions on how the old T model Fords suspension design stands up today as a competent allround off road system,
Centrally mounted to chassis transverse leaf springs front and rear for excellant articulation, positive axle location and tramp control due to torque tube drive at rear and ''A'' frame up front, and high roll centre seems to be the same qualities that are desirable in a 4WD today.
All the old T Model needed was a good set of dampers and a driving front axle, and even those were available as aftermarket options.
Bill.
Centrally mounted to chassis transverse leaf springs front and rear for excellant articulation, positive axle location and tramp control due to torque tube drive at rear and ''A'' frame up front, and high roll centre seems to be the same qualities that are desirable in a 4WD today.
All the old T Model needed was a good set of dampers and a driving front axle, and even those were available as aftermarket options.
Bill.
bill,
to be honest with you i am not real familiar with the old T models.
but from what you have described it sounds quite interesting, is the transverse leaf set up on a pivot or is it clamped in place?
i am assuming (very dangerous) that the roll centre is where the spring is attached to the chassis.
you’ve got the grey cells ticking over.
I’ve got an LJ50 that’s way past it's used by date, I might have to try this out.
Stu.
to be honest with you i am not real familiar with the old T models.
but from what you have described it sounds quite interesting, is the transverse leaf set up on a pivot or is it clamped in place?
i am assuming (very dangerous) that the roll centre is where the spring is attached to the chassis.
you’ve got the grey cells ticking over.
I’ve got an LJ50 that’s way past it's used by date, I might have to try this out.
Stu.
[quote="COOP"] By the way Mr engineering Guru maybe you better get another calculator or learn how to use it![/quote]
www.indurooffroad.com
44mm and 38mm Roll Cage Tube
Eibach Springs SAW Shocks
www.indurooffroad.com
44mm and 38mm Roll Cage Tube
Eibach Springs SAW Shocks
alot of the early fords had the A frame setup
even as late as possibly 1940
as a mates 1937 coupe when he first got it had the original A frame setup in the front
very long.......came back prob to the very middle / centre point of the chassis
should b easy enough to find some original spec drawings of the chassis on the net somewhere
even as late as possibly 1940
as a mates 1937 coupe when he first got it had the original A frame setup in the front
very long.......came back prob to the very middle / centre point of the chassis
should b easy enough to find some original spec drawings of the chassis on the net somewhere
The transverse leaf springs were clamped to the chassis crossmembers.
If memory serves me correctly the rear spring mount was much higher than the front. Old English Fords still had this system as late as the mid 1950's, but they were high,very narrow gutted cars and they used to fall over easily when cornering.
If memory serves me correctly the rear spring mount was much higher than the front. Old English Fords still had this system as late as the mid 1950's, but they were high,very narrow gutted cars and they used to fall over easily when cornering.
Bill, I remember an article by Gary Baker (Bilstein and general suspension guru) probably 20 years ago in a long dead Oz off road mag about how the 'T' model suspension was superior in certain qualities like ride and travel compared to the 'modern' semi elliptic/live axle setups.
My Dad used to also hold it up as an example of a great, workable off road/rough road setup.
The only problem that comes to mind is my general aversion to torque tubes.
They unload the near side tyre under power due to the reaction of the torque tube. The whole axle housing pivots around it.
Any one who has ever played with an old Gemini will know what I'm talking about. When Holden rallyed them, a conventional 4 link (I think it was parallel) with watts link was employed.
On another tangent, I'll dig out an article on how to promote 'warp', what we call articulation in certain racing applications.
An ideal springing medium/design was claimed to be a transverse torsion bar in a 'Z' arrangement as used in Sprintcars (which use a beam axle).
Stiff in bump, yet compliant in roll/articulation.
Should be easier to package than a transverse leaf.
What do you all think ?
Rick.
My Dad used to also hold it up as an example of a great, workable off road/rough road setup.
The only problem that comes to mind is my general aversion to torque tubes.
They unload the near side tyre under power due to the reaction of the torque tube. The whole axle housing pivots around it.
Any one who has ever played with an old Gemini will know what I'm talking about. When Holden rallyed them, a conventional 4 link (I think it was parallel) with watts link was employed.
On another tangent, I'll dig out an article on how to promote 'warp', what we call articulation in certain racing applications.
An ideal springing medium/design was claimed to be a transverse torsion bar in a 'Z' arrangement as used in Sprintcars (which use a beam axle).
Stiff in bump, yet compliant in roll/articulation.
Should be easier to package than a transverse leaf.
What do you all think ?
Rick.
300Tdi Defender 130 CC
Thanks Rick, The transverse ''Z'' bar sounds interesting. I thought about using such a device longditudally for forced articulation on Nigels hybrid, but there were too many components that got in the way.
Do you think that Unimogs suffer the problem of unloading the nearside rear wheel under power ? On my own LandRover I have attempted to replicate some of the characteristics of a torque tube by joining the 2 lower links to a single upper link, forming a long tripod that pivots on a single bushing at the transfercase crossmember. Of course not being a true torque tube, the pivot axis is not concentric with the driveshaft which is offset about 150mm to the right. I dont really know if this setup would unload the nearside tyre under power because my 2.25 litre petrol engine doesn't produce any. I would be interested in your thoughts on the tripod locating medium from an allround perspective.
Bill.
Do you think that Unimogs suffer the problem of unloading the nearside rear wheel under power ? On my own LandRover I have attempted to replicate some of the characteristics of a torque tube by joining the 2 lower links to a single upper link, forming a long tripod that pivots on a single bushing at the transfercase crossmember. Of course not being a true torque tube, the pivot axis is not concentric with the driveshaft which is offset about 150mm to the right. I dont really know if this setup would unload the nearside tyre under power because my 2.25 litre petrol engine doesn't produce any. I would be interested in your thoughts on the tripod locating medium from an allround perspective.
Bill.
Bill, welding some lengths of square tube to Volvo portal axles, and having them meet up in one single pivot point at a cross member is pretty standard in Swedish prototype triallers. Swedish (and Finnish) cars rule this class, as proven by Swedes placing 1:st and 3:d in Eurotrial this year, so it can't be that bad.
I have been toying with the idea of combining this design with your forced articulation setup. You could reduce weight and backlash significantly, since you would get away with two unis and two slipjoints less.
I have been toying with the idea of combining this design with your forced articulation setup. You could reduce weight and backlash significantly, since you would get away with two unis and two slipjoints less.
Rangerover 4.6 HSE '96
Still stockish, but with plans
Defender 110 CSW Td5 '01
Full exo cage, all MDE axles, on 9.00x16 Michelins
Still stockish, but with plans
Defender 110 CSW Td5 '01
Full exo cage, all MDE axles, on 9.00x16 Michelins
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