[Syrup]

Greetings,

Apologies in advance, but I am having extreme difficulties searching for a previous thread/post on the 'technical' reason of why we experience side-hop with the R.
IIRC it talks about the inherent design of the suspension exacerbated by the R set-up.

Does anyone know of a link to this thread/post?

Appreciate your efforts in advance.

FWIW…
As a side issue, and related to the "Everyone please read. (forum behavior)" thread, this is a real example where I have just spent and hour and 45 mins undertaking forum searches and google searches to try and retrieve the info with no avail…
Hence, as a last resort this post.

 

[SHOlover]

I believe from what I have read that sidehop is basically a sway bar and linkage problem. The stock sway is undersized in the rear causing understeer and sidehop. I also believe the subframe bushings are prone to premature failure causing unwanted play in the car as a whole. This is symptomatic of most bushings on the car.

I don't really think of it as "sidehop", more like "loosey-goosey" in the rear. It's funny because on hard corners and flowing offramps, there is almost nothing wrong with the stock set up. It really is something awesome when I give it the business around a corner. I love the moments when I hit the "Advanced" button, downshift to fifth and take a nice flowing corner. It is just when I am on uneven surfaces it feels wheird at speed. (like cool whip).

I am also pretty trashed now because it is my birthday and I have an awesome car! And Swedespeed rocks! That is all.

 

[tomedkaz]

Re: (SHOlover)

Happy Birthday man!!! 6MT FTW!!!

btw, thanks for the sidehop explaination - I have yet to experience it

 

[mad matt]

Re: (SHOlover)

Happy birthday!!!!

Alignment can also be the culprit.

Here is a little bit of info.....
http://www.google.com/custom?h...d.com

Also you're going to just have to wade through the hits you get via the google search. Good luck.

 

[SHOlover]

Thanks! My GF is passed out in my bed right now, so what do I do, grab the laptop and see what is new on SS (which I'm sure dissapoints Quagmire). Seriously, I love my R and its few flaws do not outweigh its awesomeness. R, FTW.

 

[Rho]

Re: (SHOlover)

It is my understanding that side hop is caused (at least in part) by the fact that the rear toe-in of the car changes as suspension is compressing/extending. So if one rear wheel hits a bump its toe-in angle changes (increases I believe). This will cause the car to wiggle in the direction opposite the side that the the bump was hit on.

Stiffer sway bars dramatically help side hop because they keep the rear wheels more in sync when one wheel hits a bump and the other doesn't. This means that they both have a more similar change in toe-in such that they cancel each other out a bit. And the suspension compresses less if you have to compress both wheels a little bit instead of just one.

I can honestly vouch for the "0.0 degrees of rear toe-in" fix for side hop. I was driving for a few months with practically NO side hop issues. Until recently when I swear it just came back like the flick of a switch. Turns out the dealer snuck in an alignment on me the other day and changed the rear toe-in to a more moderate value (in the center of the in-spec upper and lower limits). 0.0 degrees is still within spec; its just near the bottom of the spec limits I believe.
Properly inflated tires help side-hop a lot too.

Modified by Rho at 11:36 AM 3-14-2009

 

[JimLill]

Re: (SHOlover)

Quote, originally posted by SHOlover »

I believe from what I have read that sidehop is basically a sway bar and linkage problem. The stock sway is undersized in the rear causing understeer and sidehop.

The spring rate, damping rate, tire sidewall flex can be a poor match at times. Toe and sway adjustments can counteract it but the real cause is that while the spring rate is fixed, the 4C plays with the damping rate and although it does it in realtime, there is enough latency in the control loop, it never "gets it right" in some situations.

 

[TaiBo]

Re: Searching for technical explanation of side-hop (Syrup)

I personally have found that just changing from summer to winter tires takes away any of my noticeable side hop.

Of course my summer tires are still the pirelli tires.

 

[Needsdecaf]

Re: (SHOlover)

Quote, originally posted by SHOlover »

I believe from what I have read that sidehop is basically a sway bar and linkage problem. The stock sway is undersized in the rear causing understeer and sidehop. I also believe the subframe bushings are prone to premature failure causing unwanted play in the car as a whole. This is symptomatic of most bushings on the car. I don't really think of it as "sidehop", more like "loosey-goosey" in the rear. It's funny because on hard corners and flowing offramps, there is almost nothing wrong with the stock set up. It really is something awesome when I give it the business around a corner. I love the moments when I hit the "Advanced" button, downshift to fifth and take a nice flowing corner. It is just when I am on uneven surfaces it feels wheird at speed. (like cool whip). I am also pretty trashed now because it is my birthday and I have an awesome car! And Swedespeed rocks! That is all.

No, not really. See the explantions below.

It's the geometry of the rear suspension setup.

 

[zabto]

Are the "best" alignment specs to handle side hop posted anywhere? I found a thread linking to a defunct BVV page and didn't see it in the master mod index.

 

[JARMO]

Re: Searching for technical explanation of side-hop (Syrup)

The new Aston Martin also side-hops (without sport-suspension)
Volvo 850 also sidehopped so they made the s/v70 softer back in 1997

(it's nothing bad, it just feels strange if you don't know what it is).

 

[JRL]

Re: Searching for technical explanation of side-hop (JARMO)

Quote, originally posted by JARMO »

The new Aston Martin also side-hops (without sport-suspension) Volvo 850 also sidehopped so they made the s/v70 softer back in 1997 (it's nothing bad, it just feels strange if you don't know what it is).

My 850R with Konis and sway bars (even stiffer) NEVER sidehopped

 

[JARMO]

Re: Searching for technical explanation of side-hop (JRL)

Quote, originally posted by JRL »

My 850R with Konis and sway bars (even stiffer) NEVER sidehopped

D'oh ... 850R never sidehopped ... I said 850 ... R is different already back then ... volvo had 8 different shocks settings then

if you could read between lines you would know by now that if you stiffen the suspension the sidehop is gone

tire-pressure