[Magus2727]

What is the best adjustment to do to the rear? I have all the bells and whistles up front... C-F-M Tubular Control Arms, LCR Race Camber Plates, all Poly bushings, Eibach Sway bar w/ MOOG sway-bar links (granted fixed length..), Koni Yellow struts w/ there blue springs.

But I have nothing for the year. But my suspension Toe and Camber settings are dead on at:
-1 to -1.5 degree rear camber
0 degree rear toe.

from reading various posts and other peoples set ups these are almost the perfect settings already for the rear. What advantage would I get from getting rear toe links or adjustable rear upper arms and such? obviously I would be able to adjust it but I am not sure if i need to worry about to much adjustments.

 

[sailor]

Don't see what gain you'd get from more adjustability when you're at a setting you like already.

Wouldn't mess with it unless you're going to a poly bushed rear suspension.

Tweaking sway bar stiffness/response would be more helpful, are you on poly bushings for that now?

 

[Magus2727]

I am on poly bushings for the sway bar. that being said my other rear bushings are all factory from 2001... so likely in need of replacement. being 14 years old and having hard abuse from the suspension I have and my driving cant be kind to them. have not wanted to go poly in the event I got other arms that would come with there own joints / bushings.

 

[daspazzZX3]

I added a 26mm racecraft sb with all poly bushings and DP feels much better back there now.....

 

[Magus2727]

Eibach is already a 25mm rear sway bar. Don't think I will see much or feel much with only a 1mm difference. Also not sure if I can find that sway bar.... looks like its a rare one. I did brake 1 set of rear lower control arms already due to having a oversized rear sway bar and the poor design of non reinforced arms.

Guess I will try to do the poly bushings. Looks like on most you don't need an over sized press. Guess $130 in bushings is better than then over $500 in arms.

 

[ecugrad]

Don't see what gain you'd get from more adjustability when you're at a setting you like already.

This^ No need to fix what isn't broken.

 

[ecugrad]

Eibach is already a 25mm rear sway bar. Don't think I will see much or feel much with only a 1mm difference.

http://grassrootsmotorsports.com/articles/lean-less/

There are two primary factors that determine an anti-roll bar's torsional stiffness: the diameter of the bar and the length of the bar's moment arm. Diameter is generally the easiest concept to grasp, as it is somewhat intuitive that a larger diameter bar would have greater torsional rigidity.

Torsional (or twisting) motion of the bar is actually governed by the equation:

twist = (2 x torque x length)/(p x diam4 x material modulus.)
And since the diameter is in the denominator, as diameter gets larger, the amount of twist gets smaller. Which, in a nutshell, means that torsional rigidity is a function of the diameter to the fourth power. This is why a very small increase in diameter makes a large increase in torsional rigidity.

For example, to compare the rigidity of a stock 15mm bar to an aftermarket, 16.5mm one, simply use the equation 16.54/154. Some quick math yields the figure of 1.46. In other words, a 16.5mm bar is 1.46 times as stiff-or 46 percent stiffer-than a 15mm bar of the same design.

Add just one more millimeter to the diameter of the bar--for a total of 17.5mm--and the torsional strength skyrockets to 85 percent stiffer than the stock 15mm bar.

(17.54/15.04 = 1.85)

A little goes a long way. The Steeda RSB is both larger and easier to find.

 

[Magus2727]

This^ No need to fix what isn't broken.

Thanks. I was not sure if there is a setting that is more track desirable setting in terms of more camber or toe in (or out). Or form aftermarket arms if there are better angles (mounting points the same but the shape of the arms are different)? lighter that OEM for less unsprung weight? Better end joints? stronger for less flex or alignment changes during hard cornering?

And I guess who knows what the alignment may be after I do poly inserts in stock. Hate to spend the $ on the inserts to find out that the alignment changed enough that to get it back to what I want would require the cost of arms and toe links.

 

[Magus2727]

I will have to give that article a good read. Not sure where they are getting any of the numbers to know the difference in a 25mm to a 26mm in terms of resisting rotation on the focus.

so why stop at the 26mm and not go for Steeda's comp rear "super-stiff 28.6mm bar? Looks like it solid mounts to the lower control arm.

Edit: Looks like "felixthecat" has this one as he left a product review on Steeda's web site about it.

Edit2: also am not sure how much there is to gain in going with adjustable front swaybar links vs the fixed MOOG ones I have. It seems like for the focus that is mostly adjusted for cars with much lower stances than mine. not to change the static tension on the swaybar for race applications.

 

[ecugrad]

Thanks. I was not sure if there is a setting that is more track desirable setting in terms of more camber or toe in (or out). Or form aftermarket arms if there are better angles (mounting points the same but the shape of the arms are different)? lighter that OEM for less unsprung weight? Better end joints? stronger for less flex or alignment changes during hard cornering?

And I guess who knows what the alignment may be after I do poly inserts in stock. Hate to spend the $ on the inserts to find out that the alignment changed enough that to get it back to what I want would require the cost of arms and toe links.

Most of the time folks have rear camber arms to reduce the negative camber (I do). I'm assuming that you aren't lowered much at all with only -1.5° of camber.

I also have the big Steeda bar, works great, I'd recommend it. Just make sure its greased well.

 

[Magus2727]

Most of the time folks have rear camber arms to reduce the negative camber (I do). I'm assuming that you aren't lowered much at all with only -1.5° of camber.

I also have the big Steeda bar, works great, I'd recommend it. Just make sure its greased well.

It likes to creak otherwise... I am guessing

I am sitting on Koni Yellow shocks and there blue springs. I think that gives about 1.5" drop. I have thought about going lower in the rear but up front want to keep that height.

Having about -1.5 or so of negative camber is desirable track configuration right? around -1 to -1.5. upfront I have -2.5 to -2.6 (depending on the side).

 

[ecugrad]

It likes to creak otherwise... I am guessing

Bind, bind is BAD

I am sitting on Koni Yellow shocks and there blue springs. I think that gives about 1.5" drop. I have thought about going lower in the rear but up front want to keep that height.

Having about -1.5 or so of negative camber is desirable track configuration right? around -1 to -1.5. upfront I have -2.5 to -2.6 (depending on the side).

Those are a good starting point IMHO, fine tune to your tastes. I'm at -3° up front and -1.5° out back and will probably try to knock the rear down to -1° or less for 2015 to help with rotation (main site is SUPER grippy)

 

[Magus2727]

I want to get up to -3 or so up front with most of it coming from my tubular control arms and "zero" out the plates since the plate are easier to adjust in the padock vs the heim joints on the arms. Its just about time and warmer weather to do the work in.

I am also running on non optimal tires (a harder compounds 400 UTQG rating altra performance all-season RE960' pole positions) so need to fix that with some softer 200 tires.

after all the lack of attention to the rear suspension I thought I should look there next as suspension wise I don't think there is much else I can do up front other than adding the lower brace supports that tie in to the cross member.

 

[felixthecat]

Do you have toe-links? Makes the rear toe super easy to adjust & makes the rear feel more positive.

 

[Magus2727]

Do you have toe-links? Makes the rear toe super easy to adjust & makes the rear feel more positive.

I do not. I have not had issues with setting the toe from the factory adjustments. Since I have been able to get 0 degree in toe on the factory (thats a measured 0 degree since I guess there is a built in "trust angle" on the rear that you need some positive toe to compensate for)

the Toe links even if I set them back to 0 degree will provide a better feel.

How do you like the huge rear swaybar after getting more use on it since you rote the review on the site?

 

[sjfishon]

the rear as factory set is very good;; the only thing to watch is the large front bushing on the knuckle. they will come loose, this creates a lot of wobble on that side. you wont know till you destroy a lot of other parts, then you got a mes. if you look at the knuckle, the bushing should be in the middle,,, not touching either side. if it is its bad, i have seed new cars under 10k, and these let go in hard use. real easy to check, but very hard to fix, there is a kit, but its better to buy a new knuckle..... i know, after 800$ only one side;;;; with a newer car its not to bad but with one over 5 years old it has to be torch cut apart, see when you start changing the rear parts you sometimes put stress on the knuckle bushing and it fails,, put your money in shocks and tires leave the rest alone; good luck[][]

 

[Magus2727]

the rear as factory set is very good;; the only thing to watch is the large front bushing on the knuckle. they will come loose, this creates a lot of wobble on that side. you wont know till you destroy a lot of other parts, then you got a mes. if you look at the knuckle, the bushing should be in the middle,,, not touching either side. if it is its bad, i have seed new cars under 10k, and these let go in hard use. real easy to check, but very hard to fix, there is a kit, but its better to buy a new knuckle..... i know, after 800$ only one side;;;; with a newer car its not to bad but with one over 5 years old it has to be torch cut apart, see when you start changing the rear parts you sometimes put stress on the knuckle bushing and it fails,, put your money in shocks and tires leave the rest alone; good luck[][]

knuckle... perhaps my terminology is not correct but there is no rear knuckle. is there? you have the Hub, the upper control arm, the toe link, the lower control arm (and spring "perch"?) There is a face that the hub installs to is that what you are referring to as the knuckle? I think of a knuckle as something that also has a tie rod interface.

But regardless of terms your talking about the bushing 4A493 & 5A638?

 

[Magus2727]

http://grassrootsmotorsports.com/articles/lean-less/



A little goes a long way. The Steeda RSB is both larger and easier to find.

Not sure on that article. most is true. one thing I am not sure on is the discussion on weight transfer. a few recent articles published by NASA indicated that body role has almost no effect in actual weight transfer. body roll only impacts your camber. So to remove body roll just to stop "weight transfer" is pointless as so very little actually "transfers"

 

[ecugrad]

Not sure on that article. most is true. one thing I am not sure on is the discussion on weight transfer. a few recent articles published by NASA indicated that body role has almost no effect in actual weight transfer. body roll only impacts your camber. So to remove body roll just to stop "weight transfer" is pointless as so very little actually "transfers"

Body ROLL is a product of weight transfer.

 

[Magus2727]

Body ROLL is weight transfer

yes but the body is rolling only a few inches in worst case. and the weight is stilly more or less in the same location. you have the transfer of grip on the tires but the actual rolling of the body does not transfer physical weight from 1 tire to the other.

Let me find the article....

Pg 64 is where it starts. http://www.speednewsmag.com/Dec2014.html