Negative Camber Topic is solved

[mrbrian200]

Do also note the STI is a 3300lb car with 305hp L4 Turbo. A design based on/close to this engineering specification should hold up on a S60 but would need to be beefed up for heavier models. I have yet to see any major Volvo aftermarket suppliers do anything to correct problems rather than minorly tweak the OE design (that don't really solve issues). Powerflex is the exception. But I don't like their rear bush for this application. Their front one looks good though.

[mrbrian200]

LCA front poly bushes.
Powerflex vs Pro Parts Sweden has anyone had experience installing/test driving both: is there any functional or performance difference between the two aside from price?
Difference in hardness 5 points on the scale I doubt can be felt or heard. The design appears identical. PPS handles a broad diverse product line compared to PF which is probably explains the price difference more than anything attributable to material quality.
I'm looking for input from anyone who may have worked with both before I place an order. Because a difference of more than $100 does make you want to second guess the choice to use the less expensive ones.

Suitable weather for addressing this has returned!

I'm settling on Poly front, OE/Lemforder rear, and I'm making further refinements to my external rear bushing 'insert' between the CA and subframe to better limit the tendency of the rear of the CA to 'float' up and down without restricting the desired pivot motion at the extremes suspension travel.
There are plenty of examples of this style rear rubber bushing on other makes/models lasting the life those vehicles. My sis just got rid of an '02 Jetta with that style rear LCA bush that was absolutely fine at 180,000 miles rolling over terribly maintained rural roads it's whole life. The Volvo OE rubber is probably as good as anything else (such as the VW). I'm concluding this bush should be able to handle the pivot motion. Its the tendency to float while pivoting (because of the particular geometry of these LCAs) that takes out that rear bush. Control the float, the bush will likely last a very long time. Can't wait to get rid of the objectionable stiff feel and bump steer which has been evident since installing these specific aftermarket 'hd' LCAs, which I notice have been pulled from the vendor site where I got them.

[mrbrian200]

Found this on youtube.
Is that receiver actually necessary (circled)? As in- is there a risk of bending or breaking the LCA if the press has enough clearance fit the entire LCA? I don't see any telltale marks/scuffs in my OE LCAs (I kept them) which I would expect to see if this or a similar method is how they press them at the factory. If these LCAs were stamped steel I'd say sure, but they're not (quite beefy solid cast alloy).
I'm thinking you should be able to press it out/in against the rear bush area, maybe with a little heat and a bit of 2x4 with a half-circle cut into it so that the rear bush end sits into it snug.
I have access to a press. I'm just questioning whether it's really necessary to custom fab a receiver like the one this guy made from tube steel.

[mrbrian200]

Summarizing:
Negative camber is not absolutely necessary if you're not one to drive these vehicles at excessive speed. Negative camber helps resist vehicle roll while cornering and at speed, but it has a down side. 0 camber handles better on bumpy/uneven pavement, particularly when the road doesn't conform to NHTSA specifications for grading (if an excessively high center crown in the road exists, tires ride more on the inside edge than they would with camber set at 0, which makes the car not want to track straight over bumps/depressions in the road surface unless those imperfections span evenly across the width car). Where I live we share the neighborhood with a large Amish community. Horse traffic digs a 1 inch+ trough into asphault at the RH wheel position. Suspension set with negative (or positive) camber doesn't play nice under these conditions.

I have also become aware in recent weeks, a local alignment shop which happens to be the local go to because word of mouth states they do the 'best job', often disregards oe specs calling for positive or negative camber because of local road conditions. I confirmed this would have likely been the case on my sis' old VW which didn't handle well when she bought it. We took it to them, after which it tracked down these crappy roads just beautiful. Nothing was replaced. They only made adjustments.

It should be noted, on a SUV like the XC90, you probably want to keep negative camber at spec as higher profile vehicles have a greater tendency to roll (over!) so think twice before messing with this on a tall SUV or truck. But on low profile sedans/wagons negative camber may not necessary.

Jeremy Clarkson would push the car hard through a obstacle course set up on a glassy smooth aircraft runway, pick up on slightly lower cornering and roll resistance with zero camber and loose his cookies in a complete meltdown over it. But for the average driver in real world less than stellar US road conditions at normal/casual speeds, negative camber isn't necessarily desirable. OE designers should be careful not to watch too many of these shows. These guys are often out on a tangent that doesn't take into account real world/driver needs off the track. If they're testing a Bugatti Chiron, sure. A Volvo luxury/executive model? Probably much of what they say in these regards should be taken with a large block of salt.

Aftermarket LCAs/bushes should be avoided like the plague on P2s. The exception being if you want to tighten up steering response/dynamic toe error greased poly bushes may be used at the front position only. Keep OE bushes at the rear position. Rear poly bushes (at least the designs available as I write this) restrict suspension travel too much which adversely affects ride quality.

0 camber also appears to release some tension between 2 wheels on a given axle (depending on pavement/conditions) resulting in lower parasitic rolling resistance and slightly higher MPGs.

That's it! Case closed. Next...