46 replies to this topic

[Franklin]

(1) The extremely low center of gravity in the cars.
(2) The general smoothness of the courses (and resultant almost nonexistent vertical movement in the suspensions of the cars).

In fact, since inboard disk brakes are no longer allowed (where the torque of braking is applied directly to the chassis not through the suspension), the feature of A-arm suspension that F1 cars may be taking most advantage of is their ease of structural rigidity.

[alexbiker]

Franklin,

There are two threads of yours (OF YOURS, to translate) already discussing this.

There are videos available on the web, showing a modern F1 car on a multipost suspension testing rig. If you think that there are no bumps on F1 courses, watch the videos and notice the big round black things (known as tyres in the trade) go up and down.

So please, stop flogging this, and don't start new threads on the SAME TOPIC AS THE THREAD YOU STARTED.

Alex

[Ben]

Originally posted by Franklin
...and resultant almost nonexistent vertical movement in the suspensions of the cars

What do you think the movements are?

I have spoken to a number of Formula One engineers on this subject, including the engineer in charge of Jaguar Racing's 7-post rig. The following values are therefore the reality of F1 suspensions;

Front = up to20mm
Rear = up to 70-80mm

These are by no means negligible.

Your argument is based on these assumptions and having disproved your key assumption I am fairly sure I've invalidated your argument.

Ben

[Ray Bell]

Originally posted by alexbiker
Franklin,

There are two threads of yours (OF YOURS, to translate) already discussing this.

There are videos available on the web, showing a modern F1 car on a multipost suspension testing rig. If you think that there are no bumps on F1 courses, watch the videos and notice the big round black things (known as tyres in the trade) go up and down.

So please, stop flogging this, and don't start new threads on the SAME TOPIC AS THE THREAD YOU STARTED.

Wouldn't be a bad idea to merge them, would it?

desmo?

[McGuire]

Beam axles are not superior to IFS in camber control. They are merely less unfavorable in that regard in comparison to all their other shortcomings. With a beam axle, the front wheels are fixed at/near parallel. That is all the beam axle has going for it. In fact, the wheels cannot remain in zero camber in either bump or roll. That is exactly what beam axles *don't* do.

To see the limitations you need only watch a sprint car, in response to engine torque and chassis roll, carry its left front wheel a few hundred yards. With a beam axle, one front wheel off the ground can only leave the other in extreme positive camber. That is hardly adequate "camber control" for either wheel. This could be easily fixed with a decent IFS layout. Sprint cars would all have IFS overnight, if it were permitted by the rules.

An F1 car with a front beam axle would have exactly the same problem, even if the track were as flat as a pool table. Once the outside wheel's travel is taken up by roll, the inside wheel is pulled off the ground. The limited suspension travel of modern F1 cars is exactly why beam axles won't work.

The fact is that "camber control" is not an issue in purpose-built road racing cars today. With double unequal-length wishbones, optimized camber curves for the widest range of conditions can be obtained. For example, there are several good reasons for negative camber rate for the loaded front wheel in roll. Franklin makes an assumption here that zero camber is the ideal. That is not so. All this business about "camber control" is a red herring. If "camber control" were a real issue in F1, the first thing we would see is DeDion rear axles.

[Wuzak]

Originally posted by McGuire
Beam axles are not superior to IFS in camber control. They are merely less unfavorable in that regard in comparison to all their other shortcomings. With a beam axle, the front wheels are fixed at/near parallel. That is all the beam axle has going for it. In fact, the wheels cannot remain in zero camber in either bump or roll. That is exactly what beam axles *don't* do.

Just a quick correction.

Beam axles don't have to have zero camber, and the wheels aren't necessarily parallel.

Beam axles have nominally fixed camber. It can be positive, negative or zero camber, but fixed.

If we are going to return to beam axles, I would think it appropriate that we return to positive camber as well!!!!!!

[McGuire]

Originally posted by Wuzak


Just a quick correction.

Beam axles don't have to have zero camber, and the wheels aren't necessarily parallel.

Beam axles have nominally fixed camber. It can be positive, negative or zero camber, but fixed.

If we are going to return to beam axles, I would think it appropriate that we return to positive camber as well!!!!!!

Not to niggle, but I did specify "at/near parallel." Actually, there was a reason for all that positive camber in beam axles, ala Bugatti. I bet few people know anymore, if they even care...not that they should LOL.

[Wuzak]

Originally posted by McGuire


Not to niggle, but I did specify "at/near parallel." Actually, there was a reason for all that positive camber in beam axles, ala Bugatti. I bet few people know anymore, if they even care...not that they should LOL.

Fair enough.

What would the reason for the positive camber be? Bending?

Wasn't positive camber seen as the thing to have for some time, with F1 cars using positive camber through the '50s, and, IIRC, even into the start of the mid-engined era.

[MPea3]

Originally posted by Wuzak


Fair enough.

What would the reason for the positive camber be? Bending?

Wasn't positive camber seen as the thing to have for some time, with F1 cars using positive camber through the '50s, and, IIRC, even into the start of the mid-engined era.

i've always wondered about the positive camber thing too. in my limited experience playing around with beam axle circle track cars, i always noticed that with more caster, less negative camber or even positive camber seemed to give better handling, depending on such things as sidewall stiffness and the shape of the tread. i assumed that was because with lots of caster, the camber of the tire would "increase" toward negative as the tire was turned into the corner. the fact that the opposite was also true, that the tire went even moreso toward positive on opposite lock correction, seemed to make oversteer easier to correct.

from that i always assumed that the positive camber on older race cars was due to tire design and ease of drivability, but i'd love to hear reasons other than my own weak assumptions.

[Franklin]

Originally posted by Ben


What do you think the movements are?

I have spoken to a number of Formula One engineers on this subject, including the engineer in charge of Jaguar Racing's 7-post rig. The following values are therefore the reality of F1 suspensions;

Front = up to20mm
Rear = up to 70-80mm

These are by no means negligible.

Your argument is based on these assumptions and having disproved your key assumption I am fairly sure I've invalidated your argument.

Ben

Actually, I was guessing that if one inch up and one inch down was all that's needed there's a good possibility that a carbon fiber beam axle -- clamped in the middle so that one side can flex independently of the other -- using no springs or dampers could probably be designed to accomodate it.

[Franklin]

Originally posted by McGuire
Beam axles are not superior to IFS in camber control. They are merely less unfavorable in that regard in comparison to all their other shortcomings. With a beam axle, the front wheels are fixed at/near parallel. That is all the beam axle has going for it. In fact, the wheels cannot remain in zero camber in either bump or roll. That is exactly what beam axles *don't* do.

To see the limitations you need only watch a sprint car, in response to engine torque and chassis roll, carry its left front wheel a few hundred yards. With a beam axle, one front wheel off the ground can only leave the other in extreme positive camber. That is hardly adequate "camber control" for either wheel. This could be easily fixed with a decent IFS layout. Sprint cars would all have IFS overnight, if it were permitted by the rules.

An F1 car with a front beam axle would have exactly the same problem, even if the track were as flat as a pool table. Once the outside wheel's travel is taken up by roll, the inside wheel is pulled off the ground. The limited suspension travel of modern F1 cars is exactly why beam axles won't work.

The fact is that "camber control" is not an issue in purpose-built road racing cars today. With double unequal-length wishbones, optimized camber curves for the widest range of conditions can be obtained. For example, there are several good reasons for negative camber rate for the loaded front wheel in roll. Franklin makes an assumption here that zero camber is the ideal. That is not so. All this business about "camber control" is a red herring. If "camber control" were a real issue in F1, the first thing we would see is DeDion rear axles.

The idea that supermodifieds predominantly use beam axles because they don't have the money or engineering expertise to fully develop independent front suspension is sheer arrogance.

Camber control IS always an issue in purpose-built racecars, and it has been demonstrated by real racecars running real races in the real world that you don't always need the additional complexity of independent suspension to get it.

In fact, camber control is not why independent suspension evolved.

Independent suspension evolved to reduce unsprung weight (and thus gain the advantages stemming from that) as well as capitalize on the anti-dive and anti-squat geometry provided through control of the roll centers.

Carbon fiber suspension components may negate the unsprung weight advantage formerly held by independent suspension.

[Ben]

Originally posted by Franklin


Actually, I was guessing that if one inch up and one inch down was all that's needed there's a good possibility that a carbon fiber beam axle -- clamped in the middle so that one side can flex independently of the other -- using no springs or dampers could probably be designed to accomodate it.

Yeah you could probably do a lot of thing. Why would this be better? This isn't a beam axle it's a swing arm and they are not very useful for F1. Heard of jacking?

Look at the last couple of Williams and Jag F1 cars. They have double wishbone suspension systems with roll centres below the ground. The only way I know of achieving a below ground roll centre with a beam axle is a mumford link. Unfortunately a mumford link isn't the most aerodynamic of devices.

Given that the requirements for many teams seems to be a below ground roll centre, how would you acheive this without any significant aerodynamic penalty?

Ben

[McGuire]

Originally posted by Franklin
Independent suspension evolved to reduce unsprung weight (and thus gain the advantages stemming from that) as well as capitalize on the anti-dive and anti-squat geometry provided through control of the roll centers.

BS, Frank. Independent suspension was developed to obtain independent wheel control. With a beam axle that is lost.

Anti-dive and anti-squat geometries cannot be achieved through "control of roll centers." Here you have lapsed into technobabble. In fact the geometeries really have nothing to do with each other. AS/AD geometries relate to the chassis' longitudinal plane while roll centers relate to the lateral plane. 

Anti-dive and anti-squat geometries are just as easily achieved with beam axles as with independent suspension. On a beam front axle: if you locate the forward pivot of the upper radius rod ahead the the forward pivot of the lower radius rod, you have anti-dive. Or, you can mount the radius rods closer together at the frame than at the axle, on convergent axes with a line projected from the front tire patch to the vehicle CG.

To achieve anti-squat on the other end of the car, it works exactly the same way in reverse layout.  For example, drag cars often have considerable anti-squat adjusted into the rear four-link. The higher the projected intersecting point of the two trailing arms, the greater the anti-squat percentage. For a guy who talks a lot of drag racing and beam axles, you don't seem to know squat about either one.

[McGuire]

Originally posted by Franklin


Actually, I was guessing that if one inch up and one inch down was all that's needed there's a good possibility that a carbon fiber beam axle -- clamped in the middle so that one side can flex independently of the other -- using no springs or dampers could probably be designed to accomodate it.

Congratulations, you have just invented the independent front suspension used on the 1939 Studebaker (The "Planar" system developed by Delmar G. "Barney" Roos).

With your composite beam fixed in the center and providing the spring medium, you will find that it needs at least as much damping as a conventional steel spring. Composite springs have been around for twenty years so the experience base is rather extensive. Maybe you could read up on it sometime. You will also find that your setup needs an upper or lower wishbone to support the upright vertically, and a means of longitudinal location as well.

[Wuzak]

Originally posted by McGuire
Composite springs have been around for twenty years so the experience base is rather extensive.

Haven't Corvettes got composite (fibreglass) leaf springs, at least at one end? How long have they used them?

[Ben]

Originally posted by Franklin



Independent suspension evolved to reduce unsprung weight (and thus gain the advantages stemming from that) as well as capitalize on the anti-dive and anti-squat geometry provided through control of the roll centers.

As has been pointed out, this is pure technobabble.

Anti-dive and anti-squat relate to the side view geometry (i.e. pitch centres) not the front view geometry that defines the roll centre.

You clearly don't understand the basics of suspension kinematics so why do you feel you are in a position to propose a paradigm shift in Formula One's state-of-the-art in this area?

Once again, how many road racing cars have you built? How many have you engineered and adjusted the setup on? If the answer is none please do us a favour and consider the opinion of those of us who have.

Ben

[McGuire]

Originally posted by Wuzak


Haven't Corvettes got composite (fibreglass) leaf springs, at least at one end? How long have they used them?

1981.

[Franklin]

Originally posted by Ben


As has been pointed out, this is pure technobabble.

Anti-dive and anti-squat relate to the side view geometry (i.e. pitch centres) not the front view geometry that defines the roll centre.

You clearly don't understand the basics of suspension kinematics so why do you feel you are in a position to propose a paradigm shift in Formula One's state-of-the-art in this area?

Once again, how many road racing cars have you built? How many have you engineered and adjusted the setup on? If the answer is none please do us a favour and consider the opinion of those of us who have.

Ben

Okay, call it "converging the pivot axes of the front and rear wishbones." If that sounds like technobabble to you take it up with Len Terry, someone who HAS built a bunch of road racing cars.

And why do you think FIA banned rigid suspensions in F1 cars? Do you think F1 cars have always had functional (operable) spring/shock units installed in them?

[Jordan191]

watching the 1993 French GP I heard mention of Lotus using a reactive ' spring less ?!?! ' suspension system. The commentators mentioned it was the most advanced system in F1, based on comments from Patrick Head. Williams were supposedly going to run one in 1994 had the regs not changed.

btw oval cars of that type can use solid axles cause they only turn left and use asymetrical tyres/camber. That would *never* work in F1.

[MPea3]

Originally posted by Jordan191
btw oval cars of that type can use solid axles cause they only turn left and use asymetrical tyres/camber. That would *never* work in F1.

agreed. on a circle track it's simple, tough as nails, and easy to adjust though. it continues to be used in circle track because it works.

[Wuzak]

Originally posted by Franklin


Okay, call it "converging the pivot axes of the front and rear wishbones." If that sounds like technobabble to you take it up with Len Terry, someone who HAS built a bunch of road racing cars.

And why do you think FIA banned rigid suspensions in F1 cars? Do you think F1 cars have always had functional (operable) spring/shock units installed in them?

Yes.

When have they not??

[Wuzak]

Originally posted by Jordan191
watching the 1993 French GP I heard mention of Lotus using a reactive ' spring less ?!?! ' suspension system. The commentators mentioned it was the most advanced system in F1, based on comments from Patrick Head. Williams were supposedly going to run one in 1994 had the regs not changed.

btw oval cars of that type can use solid axles cause they only turn left and use asymetrical tyres/camber. That would *never* work in F1.

I believe that they were referring to hydraulic active suspension. Williams and Benetton, at least, also had active suspension, though I'm not sure what they used for springing.

[Ben]

Originally posted by Franklin


Okay, call it "converging the pivot axes of the front and rear wishbones." If that sounds like technobabble to you take it up with Len Terry, someone who HAS built a bunch of road racing cars.

And why do you think FIA banned rigid suspensions in F1 cars? Do you think F1 cars have always had functional (operable) spring/shock units installed in them?

What's Len Terry got to do with it?

You really have issues when someone points out that you were wrong don't you. Pitch centres and roll centres are fundamentally different things. I'm sure Mr Terry would agree on that.

The FIA actually banned 'rigid' suspensions at the behest of Ferrari who thought a rigid approach was what Lotus was doing when they were actually doing the twin-floor Type 88. This is covered very well in Wright's F1 Technology.

Having corrected the history of how that rule came to be, I will agree that F1 cars have at times run virtually solid suspensions as a band-aid. However I would ask you to accept that as a result of the active suspension era they began to learn how to harness highly pitch sensitive aerodynamics and also how to go some way to replicating this with mode decoupled systems (third springs, etc). This is why we have now seen a return to a degree of suspension movement as 7-post rigs allow a greater understanding of this problem.

Your views on rock solid F1 suspension are straight out of the late 1980s. Please ask an F1 rig engineer if you don't (as I suspect you won't) believe me.

Ben

[McGuire]

Originally posted by Franklin


Okay, call it "converging the pivot axes of the front and rear wishbones." If that sounds like technobabble to you take it up with Len Terry, someone who HAS built a bunch of road racing cars.

Sorry, but I have to call BS on you here Fwank. There was no need for the development of independent suspension as a path to anti-dive/anti-squat. These geometries are just as easily obtained with beam axle suspension. Nor do I believe for a second that if Len Terry checked in here, he would take up with any of your positions. I've read his stuff, and I know his cars. They share nothing with any of the theories you have advanced here.

[Powersteer]

Small as F1 suspension travel are but they sure move fast. At the rate F1 cars do corners and going over the curbs tey could only move far more quickly than normal road cars. Usually this is something that cannot be told by the normal eye. Only way to see is to use a beam axle instead


I guess positive camber was used because tyres at that time were narrow. Todays tyres are wide so a positive camber would distort the edges of the tyre more and it would fold in the middle of the contact patch area. Many years ago i think it was Goodyear who use to promote thier twin internals in the tyre to prevent this folding or rupturing on production cars.

[Franklin]

Originally posted by McGuire


Sorry, but I have to call BS on you here Fwank. There was no need for the development of independent suspension as a path to anti-dive/anti-squat. These geometries are just as easily obtained with beam axle suspension. Nor do I believe for a second that if Len Terry checked in here, he would take up with any of your positions. I've read his stuff, and I know his cars. They share nothing with any of the theories you have advanced here.

"Converging the pivot axes of the front and rear wishbones" is a direct quote from page 148 of"Racing Car Design And Development" by Len Terry.

On page 142, referencing the illustration on pages 140 and 141, Terry discusses an alternative to the de Dion rear suspension (as "...like any beam axle system, it keeps the tyres square to the effective line of the road surface at all times" [page 138]) based on the idea of introducing a degree of freedom into the beam through use of central sliding joint.

[Ben]

Originally posted by Franklin


"Converging the pivot axes of the front and rear wishbones" is a direct quote from page 148 of"Racing Car Design And Development" by Len Terry.

On page 142, referencing the illustration on pages 140 and 141, Terry discusses an alternative to the de Dion rear suspension (as "...like any beam axle system, it keeps the tyres square to the effective line of the road surface at all times" [page 138]) based on the idea of introducing a degree of freedom into the beam through use of central sliding joint.

Great quote from Terry's book (which I read when I was still at high school BTW). However no one was arguing that that is how you achieve anti-squat/dive. You said it was altered by changing the roll centre which is clearly rubbish and we were telling you you were wrong, we all knew it was actually altered by converging the pivot axis'.

Anti features are just as easy to acheive on a beam axle. Indeed Arthur Mallock incorporated asymmetric anti-squat to offset the torque reaction and keep the diffuser square to the road.

Ben

[McGuire]

Originally posted by Franklin


"Converging the pivot axes of the front and rear wishbones" is a direct quote from page 148 of"Racing Car Design And Development" by Len Terry.

On page 142, referencing the illustration on pages 140 and 141, Terry discusses an alternative to the de Dion rear suspension (as "...like any beam axle system, it keeps the tyres square to the effective line of the road surface at all times" [page 138]) based on the idea of introducing a degree of freedom into the beam through use of central sliding joint.

First, the quote you cite first merely describes how AD/AS is accomplished with wishbones. Where does Terry say that independent suspension is required to incorporate AD/AS geometry? If the book does state that, it is clearly in error.

Next, where does Terry offer that a non-independent, rigid beam axle might offer advantages over independent suspension on race cars such as those found in 2004? Considering the book was written in 1973 I will offer you some leeway, but please understand you have already long since exhausted everyone's patience.

[Rat_Fink]

Amen to that

[Franklin]

Originally posted by McGuire


First, the quote you cite first merely describes how AD/AS is accomplished with wishbones. Where does Terry say that independent suspension is required to incorporate AD/AS geometry? If the book does state that, it is clearly in error.

Next, where does Terry offer that a non-independent, rigid beam axle might offer advantages over independent suspension on race cars such as those found in 2004? Considering the book was written in 1973 I will offer you some leeway, but please understand you have already long since exhausted everyone's patience.

The general configuration of open wheel mid-engine formula cars has remained unchanged since 1973, aside from the fact placement of the radiator in the nose has completely disapeared with radiators in the sidepods now being used exclusively. Rather than adopting more complex systems for maintaining camber control in independent suspension systems (such as Norbett Hamy's Trebron Double Roll Centre), the solution that has evolved is simply to make work conventional suspension systems with very small up and down movement.

[Ben]

Answer the damn question Franklin, or leave.

Ben

[Wuzak]

Originally posted by Franklin


The general configuration of open wheel mid-engine formula cars has remained unchanged since 1973, aside from the fact placement of the radiator in the nose has completely disapeared with radiators in the sidepods now being used exclusively. Rather than adopting more complex systems for maintaining camber control in independent suspension systems (such as Norbett Hamy's Trebron Double Roll Centre), the solution that has evolved is simply to make work conventional suspension systems with very small up and down movement.

Surely the small suspension movement has little to do with camber control, and more to do with body control? Required to maintain the body in relation to the ground, and therefore maintain the downforce generated by the underbody?

And isn't some camber change with body roll desireable??

[alexbiker]

Originally posted by Franklin


Rather than adopting more complex systems for maintaining camber control in independent suspension systems. . . . . the solution that has evolved is simply to make work conventional suspension systems with very small up and down movement.

So you're suggesting that short travel suspension is only because of camber control?

Again, total BS, coupled with a nauseatingly bad approach to grammar. . . .

Notice above that I have quoted only the portion of your post that is of interest, not the whole damn thing.

Alex

[mart]

...after a trip around Jordans factory just before christmas, I'd just like to ask Franklin if flex in the tyre walls & struts counts as suspension as that's all the Jordans have up front (no suspension mechanism as such)...

[alexbiker]

Originally posted by mart
...after a trip around Jordans factory just before christmas, I'd just like to ask Franklin if flex in the tyre walls & struts counts as suspension as that's all the Jordans have up front (no suspension mechanism as such)...

I'm afraid that is not and cannot be true.

From the technical regs:

Cars must be fitted with sprung suspension. The springing medium must not consist solely of bolts located through flexible bushes or mountings. There must be movement of the wheels to give suspesnion travel in excess of any flexibilty in the attachments

Therefore, flex in the system does not constitute enough suspension for the FIA. There must be a designed in system such as a coil spring or torsion bar.

http://www.atlasf1.c...e=drb04090375-2

This picture shows the suspension pushrod, at roughly 45 degrees to the vertical, which most likely operates a torsion bar. Others can tell you definitely.

Alex

[alexbiker]

Originally posted by Wuzak


I believe that they were referring to hydraulic active suspension. Williams and Benetton, at least, also had active suspension, though I'm not sure what they used for springing.

Williams used no springs at all. The "spring" was fully hydraulic, compressing and rebounding the suspension in response to sensed forces on the suspension pushrods - maintaining both a perfect ride height and attitude over curbs etc. This is why Patrick Head has been quoted referring to the car as featuring "active ride" rather than active suspension. One mechanic, can remember who, recalled the instant feeling of dejection on walking past the Williams garage and seeing them "exercising" the car - running the suspension through exactly the same movements it had undergone in a recent test lap. He knew that there was nothing to compete.

IIRC, Bennetton used coil springs and an active damper, a system with some advantages, but nothing approaching the total engineering perfection of the FW14B.

Alex

[mart]

I'm afraid that is not and cannot be true.

sorry...are you saying that Tony (our guide) lied & so did my eyes?

The car had all of it's bodywork/inspection covers off plus he explained it all to us before taking us off to show us how they made the struts).

I'm guessing they won't be the only team using that approach either...

[alexbiker]

Sure he wasn't talking about rollers (dummy cars)?

And the idea an F1 staffer might lie? The mere thought!

It wouldn't be legal to do that, and the pushrods are there - they must be there to push something. This is, after all, quite easy to scrutineer!

Alex

[Ben]

Originally posted by mart
...after a trip around Jordans factory just before christmas, I'd just like to ask Franklin if flex in the tyre walls & struts counts as suspension as that's all the Jordans have up front (no suspension mechanism as such)...

What were the pushrods connected to?

I think you've got the wrong end of the stick or been told a bit of a fib.

Ben

[McGuire]

Originally posted by alexbiker


Williams used no springs at all. The "spring" was fully hydraulic, compressing and rebounding the suspension in response to sensed forces on the suspension pushrods - maintaining both a perfect ride height and attitude over curbs etc. This is why Patrick Head has been quoted referring to the car as featuring "active ride" rather than active suspension. One mechanic, can remember who, recalled the instant feeling of dejection on walking past the Williams garage and seeing them "exercising" the car - running the suspension through exactly the same movements it had undergone in a recent test lap. He knew that there was nothing to compete.

IIRC, Bennetton used coil springs and an active damper, a system with some advantages, but nothing approaching the total engineering perfection of the FW14B.

Alex

Point of clarification before any readers jump to conclusions: while an active ride car has no *springs* in the commonly understood sense, it certainly does have *suspension* ...in the case of the Williams FW14B, an extremely sophisticated suspension, as you describe here.

[McGuire]

Originally posted by mart


sorry...are you saying that Tony (our guide) lied & so did my eyes?

The car had all of it's bodywork/inspection covers off plus he explained it all to us before taking us off to show us how they made the struts).

I'm guessing they won't be the only team using that approach either...

The Jordan EJ12/EJ13 uses a double wishbone front suspension with pushrods, torsion bars, and dampers. The guide was either misinformed (more than likely a hospitality or PR rep rather than a technical person) or pulling your leg.

[mart]

Originally posted by McGuire

The Jordan EJ12/EJ13 uses a double wishbone front suspension with pushrods, torsion bars, and dampers. The guide was either misinformed (more than likely a hospitality or PR rep rather than a technical person) or pulling your leg.

Depends on how you look at it (Axelbiker, I'm on about the same thing as you)...in this case, the sprung part of the suspension is taken up by the arms & tires. The damper then dissipates the energy stored in the wishbones via the push rods.

The torsion bar's not really a suspension (if you counting that purely as shock absorbtion ) component as it's job is to transfer the cornering forces & balance the car in a turn.

[kos]

mart, torsion bar is just another form of spring, i think that you're mistaking "torsion bar" with "antiroll bar"

my Renault 19 has torsion bars instead of coil-springs in the rear suspension - do you want to say that it has no rear suspension at all?

[Wuzak]

Originally posted by mart


Depends on how you look at it (Axelbiker, I'm on about the same thing as you)...in this case, the sprung part of the suspension is taken up by the arms & tires. The damper then dissipates the energy stored in the wishbones via the push rods.

The torsion bar's not really a suspension (if you counting that purely as shock absorbtion ) component as it's job is to transfer the cornering forces & balance the car in a turn.

I don't know what you mean....


The pushrods are connected to the torsion bars, which are springs. The torsion bars take the loading from the wheel via the pushrod. The pushrod is also connected to the dampers, which damp the wheels' motion. Also connected to the pushrods via some mechinism is the anti-roll bar.

It is true that a large component of the springing of the car is through the tyres, but it is not the total amount.

I do not believe that the wishbones themselves are used for springing, and I think it less than desirable. In any case, the pushrod is connected at the outboard end of the lower wishbones, and at the top to the torsion bar spring/damper/anti roll bar assembly. Not much chance to transmit the loading into the wishbones in that direction.

[McGuire]

Originally posted by mart


Depends on how you look at it (Axelbiker, I'm on about the same thing as you)...in this case, the sprung part of the suspension is taken up by the arms & tires. The damper then dissipates the energy stored in the wishbones via the push rods.

The torsion bar's not really a suspension (if you counting that purely as shock absorbtion ) component as it's job is to transfer the cornering forces & balance the car in a turn.

With some detail differences, all F1 cars including Jordan now use the same general front suspension layout. Torsion bars serve as the spring medium, connected via the same pushrod and bellcrank linkage as the dampers. The wishbones are specifically designed not to bend or flex in response to bump or roll, but to be as rigid as possible, pivoting on their chassis mounts via flexures.

Formula 1 Technical Analysis 2002/2003 by Giorgio Piola includes a number of excellent illustrations and explanations.

[EvilPhil]

Plus as far as i am aware it is a legal requirement in F1 that all suspension 'processes' take place via springs etc... flex alone is not allowed. I guess this is to stop the cars becoming go-karts.

[Ben]

Originally posted by mart


Depends on how you look at it (Axelbiker, I'm on about the same thing as you)...in this case, the sprung part of the suspension is taken up by the arms & tires. The damper then dissipates the energy stored in the wishbones via the push rods.

The torsion bar's not really a suspension (if you counting that purely as shock absorbtion ) component as it's job is to transfer the cornering forces & balance the car in a turn.

A torsion bar is a spring. A coil spring also operates in torsion if you analyse the deflection.

Your last paragraph simply doesn't make sense I'm afraid.

Ben