contradiction in the movement of a 4 link rear end?

[Sam_Q]

the other way to overcome this limitation is to run good bushes/joints in all the links except the top, upper right hand side bar which use drill holes into the original rubber bush to basicly stop it doing anything other than be a safety link. Many have recommended this setup now. I am sure many of those aftermarket 5 link owners would be pissed needing an original looking bar under their car.

Also of note I hear some of the aftermarket 5 link kits are coming from china and are made from solid aluminium bars. Makes me wonder if that is true and the bars are what is providing the deflection that woudnt the aluminium fatiuge over a long time period?

[fangsport]

the other way to overcome this limitation is to run good bushes/joints in all the links except the top, upper right hand side bar which use drill holes into the original rubber bush to basicly stop it doing anything other than be a safety link. Many have recommended this setup now. I am sure many of those aftermarket 5 link owners would be pissed needing an original looking bar under their car.

Also of note I have some of the aftermarke 5 link kits are coming from china and are made from solid aluminium bars. Makes me wonder if that is true and the bars are what is providing the deflection that woudnt the aluminium fatiuge over a long time period?

why buy those cheap looking Chinese cast offs when it is easy to make you own?
assuming Australia got fwd camrys and mazda323's circa '93, there are some very nice adjustable track/castor/toe rods in the rear of them.
$20 worth of parts and $80 to get cut and welded as i needed them done then and not later as a perky.
$100 to have adjustable top arms and panhard rod

[The Real Roadrunner]

except the top, upper right hand side bar which use drill holes into the original rubber bush to basicly stop it doing anything other than be a safety link. Many have recommended this setup now.

the only big problem i can see with this is that the car will rear steer differently from one side to the other, ie the car will turn differently left to right depending on the amount of turnin and your swaybar settings.

its a difficult thing to overcome but the only real way to get rid of the excessive deflection in the housing is by running longer top arms (similar length to the lowers)

then the amount of deflection will be reduced substantially

your other option is to change over to an upper A arm setup but you would have to pay alot of attention to your lower arm angles to get rid of the rear steer this would then induce.

how far do you want to go with it? could spend thousands or just deal with the fact that it is what it is.

cheers
linden

[Gold28]

Don't forget that each side of the axle will rotate around a theoretical center which is the projected intersection of the upper and lower arms. This being a long way forward in the chassis means that they will only produce very small rotations for a realistic suspension movement.

That arguement stands for most standard suspension designs. Unfortunately when you lower a car, the theoretical center moves aft and the problem gets worse.

Any solution will unfortunately only be a compromise. Using the 3 link method is probably a good solution for drag racers as they can select the side that does less work and drop that link. Circuit racers unfortunately don't have that luxury and really should consider the structural effects on the chassis before rosejointing a solid axle. Having said that a circuit racer will normally be set up with low CofG, high roll stiffness and run on a nice smooth track. So a one wheel bump situation isn't as bad.

For a road car, I would consider rose jointing the lower arms only. Sure make the upper arms adjustable but make sure they have some compliance otherwise you will eventually find your chassis cracking which is gonna be a lot wose for handling than a couple of rubber bushes.

Plus rep to you though for raising an, interesting arguement.