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Alfa 159 1.9 JTDm Sportwagon
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You would have to have one made as there has never been one available before.
 

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Yes they do.
Basically the same setup as the 156.
 

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sure double wishbone or single or multi linkage is irreverent when your talking about tower braces, they are designed to keep the shocks tight. with ?? wishbone is there to keep the wheels flat on the floor...

Ill get onto my lad in the UK and see if he is interested in designing one and building one... or if he even can.
 

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To an extend I feel the 156 and 166 setup need braces even more if you look at the way the upper which bones is mounted
 

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sure double wishbone or single or multi linkage is irreverent when your talking about tower braces, they are designed to keep the shocks tight. with ?? wishbone is there to keep the wheels flat on the floor...

Ill get onto my lad in the UK and see if he is interested in designing one and building one... or if he even can.
..cool. just make sure they're not blue or orange or something..! :thumbs:
 

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But why? On a car with Macpherson struts, I can see how they can stop the tops of the struts getting closer together on big bumps, thereby preserving camber control better. On a car with double wishbones, surely the top of the strut can go where it likes (OK, you'd still want room for the engine:)!) and the wishbones control the camber? There won't be much load on the top wishbone because the strut is feeding all the bump load into the shell.
 

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But why? On a car with Macpherson struts, I can see how they can stop the tops of the struts getting closer together on big bumps, thereby preserving camber control better. On a car with double wishbones, surely the top of the strut can go where it likes (OK, you'd still want room for the engine:)!) and the wishbones control the camber? There won't be much load on the top wishbone because the strut is feeding all the bump load into the shell.
putting a top strut on a car doesnt just keep the angle of the wheel more aligned but more keeps the wheels closer by helping to preventing the body roll and flex in the metal.. the point of a double wishbone setup is that it helps to keep the wheel in an upright alignment (or what ever alignment you set it to)
For example, if you go over a bump the wheel will be more likely to keep its alignment using a strut brace will prevent (or help) the wheels from wondering when cornering and keep the front end more ridged. the wishbones are mearly linked to the body which its self can flex and move where as if you link the 2 units together (and to the body if possible) then they will not move and will hold shape better.
if you go to the UltraRacing website there are example of dozens of bars that can be had and where they go to make a cars body more ridged..

perfect example is the Toyota Levin with Superstrut (which i own) which is classed as one of the best suspension setups ever designed. its a multi linkage system.. and Toyota even fit a 3 point tower brace for exactly that reason, to stop body flex and wheel misalignment and miscontact in cornering.

As for the camber, that is controlled byt the camber controle arm not the wishbone (Alfa might have that incorporated with the wishbone)

here is an example of what the strut bar does...
http://throwdownperformance.com/index.php?main_page=product_info&products_id=540

hope this informs a little ... :)
 

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Nah, sorry, not buying it! I agree that bracing the tops of the struts on a car with Macpherson struts is helpful, up to a point, depending on how stiff the original shell is. It can't do much for the roll stiffness (which is primarily governed by the springs and anti-roll bars). It won't stiffen the shell much in torsion either. For that, you'd need to also brace it back to the bulkhead or some convenient shear panel (like the 3-point brace you mention). All the strut-to-strut braces really do (as in the top little animations on that link you provided) is keep the strut tops the right distance apart, which will help, in minute amounts, with camber control. I agree though, being much shorter, that the bottom arm is more significant at doing that - and it's one of the reasons why strut braces don't really do very much on road cars with rubber bushed suspension because you normally get FAR more movement in the rubber bushes than you ever get in the shell.

Double wishbones don't just keep the wheels pointing where you want them, they're really good when it comes to controlling the position of the roll centre as the car rolls. Struts aren't so good at that.

I think the problem with the second animation on that site - showing the car going into roll, is that the amount of twist generated in the body depends on the relative roll stiffnesses of the front and rear suspensions. If they both have the same roll stiffness, there won't be any twist down the shell (like a Morgan - they have famously floppy structures, but (other than for ride comfort, shakes and rattles) it doesn't matter much because the roll stiffness is similar at both ends). In the animation, it seems to suggest that there will be less flex in roll after fitting a strut brace (which there might be a smidgin less), but the bulk of the twist comes from movement between the (say) left hand front corner and right hand rear corner, and I can't see how the strut brace can't do much for that (other than the three point ones feeding some of the load into the bulkhead - which can do a bit more).

In the case of a 166/156, (and unlike the Toyota), the strut istelf plays no part in determining the suspension geometry - which is all done by the two wishbones, the steering rack and the upright. I don't know if the front subframe on a 166 is rubber-mounted (I've a feeling my wife's old 156 one was), but if it is, I've a feeling there will be little point in tying the strut tops together when the subframe to which all the suspension is attached is free to move on its rubbers.
 

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No the subframe's mount solid on the 156 and 166
 

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In a situation where strut tops have became closer to each other (1-2cm), hence causing big negative camber, strut brace/bar would help? Is it the only way how to fix this kind of camber problem?
 

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On a double wishbone setup (like the 166) the struts play no part in camber control. You could wedge the tops of the struts under the door mirrors and the camber would be the same. Camber is controlled by the subframe, the upright, and the top and bottom wishbones. Certainly, in a MacPherson strut car, if the strut tops moved in by that amount on a big bump, a strut brace would help greatly.
 
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The only reason I want an upper strut brace is too stop the car flexing inbetween the suspension turrets. And this also stops a lot of the rattles and noise you get from the car moving over bumps etc. I know this works as on a 155 I've been in all the rattles stopped as the brace was fitted.
 

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On a double wishbone setup (like the 166) the struts play no part in camber control. You could wedge the tops of the struts under the door mirrors and the camber would be the same. Camber is controlled by the subframe, the upright, and the top and bottom wishbones. Certainly, in a MacPherson strut car, if the strut tops moved in by that amount on a big bump, a strut brace would help greatly.
The top wishbone is part of the strut top assembly on the 156 147 GT and 166 so movement of the turrets will influence the geometry.
 

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The only reason I want an upper strut brace is too stop the car flexing inbetween the suspension turrets. And this also stops a lot of the rattles and noise you get from the car moving over bumps etc. I know this works as on a 155 I've been in all the rattles stopped as the brace was fitted.
..i think what damien says is on the money. When the suspension turrets can flex vertically in relation to each other in effect they become part of the suspension . This means the springs/dampers can't do their job properly as the body flex becomes part of the spring rate.

The squeaky door seals in the 166 highlight the body flex.. you'll notice it if you drive slowly over a speed bump with one side of the car (not that body flex is unique to the 166.. the squeaky seals just highlight it.. ! )

Some of the braces seem to be hinged at either side.. these are likely designed to stop the top of the struts moving towards each other and thus control camber as mentioned, but they'd probably be little help in a 166.

A brace that was designed to counteract the vertical movements of the suspension turrets in relation to each other would be helpful i think.. in theory an x-type frame between the turrets for instance, though there is the inconvenience of an engine in the middle :)

But it should still be possible to design something practical to reduce this flex.. not sure if it would be worth the trouble, but it's interesting all the same..
 

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Yes that will be ideal.
 
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