Rear Sway Bar Upgrade: The Single Best Suspension Mod for your Focus RS
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When I spoke to my suspension gurus, I was panicking that my oem endlinks would cause issues, etc, etc.
They told me to relax and let them do their thing.
So I did and in a few months I have the 2way suspension for a year with the HR bars and OEM endlinks and the ride is sublime.
Probable the best upgrade I did to the car.
They told me to relax and let them do their thing.
So I did and in a few months I have the 2way suspension for a year with the HR bars and OEM endlinks and the ride is sublime.
Probable the best upgrade I did to the car.
Someone might be able to clarify deeper, but I always thought (this is usually with aftermarket springs/suspension) with the car on on the ground (or full weighted suspension) the endlinks to the sway bars should be adjusted to a zero preload. Using the OEM links on a lowered vehicle will actually have the suspension/sway bars possibly work against you (unless you can achieve zero preload).
This was my understanding as well.
That's what I thought as well. This is why I bought the adjustable Whiteline endlinks before I installed my KW DDCs. However, when I lowered the car onto the ramps, the distance between the sway bar and strut mounting point was too great, indicating I'd actually have to run a longer endlink. There was no way I would be able to get the correct endlink long enough, as there was not enough threading on either end, so one end actually came out when trying to lengthen:
So I ended up setting the endlinks about the same length as the OEM ones. Haven't had any issues.
How much did you lower the car?
Not a lot. I set the coilovers at max height in both front and rear. So when all was said and done, I'm about a finger width (maybe a tad less) fender gap all around.
Gotcha. I seem to see really hit & miss comments about endlink length, it's almost as if Whiteline has 2 different lengths. I've got a full set sitting in the garage with the Mountune springs & revised OEM dampers, I just need my friend's lift (and help) to get it done. And then I'll know which group my endlinks fall into lol.
Haha! Part No. on mine was KLC163, which I believe is the part that comes with their front sway bar kit. Actually got them at Amazon, as they were only like $90 at the time: https://smile.amazon.com/gp/product/B00N9GGE6G/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1. Having a friend with a lift will definitely help. I did it all myself with just jacks and jack stands. Took me the better part of two days. Although, most of the issues I encountered were related to the damper portions (particularly the top hats), and multiple trips to different dealers to replace bolts that were either stripped or that I didn't feel comfortable reusing.
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This is a pickle.
When lowered:
If you adjust the FSB for zero preload, check contact with the lower control arm at full lock
You may have to adjust for no contact . . .
* this is a quite important setting, and perhaps not worthy of being buried in the RSB thread*
When lowered:
If you adjust the FSB for zero preload, check contact with the lower control arm at full lock
You may have to adjust for no contact . . .
* this is a quite important setting, and perhaps not worthy of being buried in the RSB thread*
So I did end up grabbing the same end link kit > KLC163. Initially I was measuring out the stocks which were right at 12" and adjusted the WL links the same for the install. I swapped my OE springs for the Mountune Black (0.5" drop/15mm) and while in the air I had to actually shorten the endlinks some for the install. But thought it could change once I had it on the ground to adjust preload.
Put it on the ground and only had to adjust it a little before I got zero preload on the FSB. Set the nuts to tight and went and got an alignment
Only put a couple miles on this so far....
This I need to do and pay attention on this just to make sure (didn't see rubbing). Try and report back after about 1k (not a bunch of driving when working from home).
Based on the differing comments/experiences with front sway bar endlinks it seems to indicate that there isnt a simple answer as to what does or doesnt work.
General rule: swaybars should be unloaded from side to side, ie, in a null position, bc they are only intended to be affecting the suspension (increasing spring rate) when cornering. Note: if the swaybar was statically loaded equally on each side it would "in effect" be balanced side to side but it would be continuously statically loaded adding spring rate in normal driving. This tends to transmit road noise and harshness into the car......especially if the bushings ARE NOT FREE FLOATING IN THE D BRACKETS...ie, RS oem swaybar bushings.
Almost all of the posts cite various combinations of sway bar brand (and bushing), and different struts (oem and aftmkt), so it is difficult to narrow in on why some work on one combination and not on another. With different variables it is nearly impossible to have a single answer.
I believe the critical issues are the endlink mounting position on an aftrmkt strut vs oem strut, the relative endlink mounting position of the aftmkt swaybar vs oem swaybar, and the "free floating" bushing common on aftmkt swaybars and the "semi-fixed/ restricted oem bushing (which determinds the orientation of the oem bar).
On my 2016 RS with Mountune black springs, on original front struts and swaybar/bushing, the factory endlinks were preloading the swaybar (downward, too long ). I purchased a used set of WL endlinks from another member, but dont know the pn. If i had changed the front bar to an afftrmkt bar with a "free floating" design bushing any reasonable length endlink, including possibly a stock endlink would have worked bc the bar would have freely rotated to a position allowing the bar to be set with no side to side or overall preload.
The issue with the "semi-fixed" oem bushing is that it creates a preloaded static condition (both sides) using the oem bar with oem struts and lowering springs. Adding an aftrmkt bar with a floating bushing overcomes the semi-fixed bushing issue by increasing the rotation range of the endlink mounting position.
This does not answer which is the correct WL or other brand of endlink to use with which combination of springs, struts, and swaybars...and I suspect it is going to boil down to what part combination you are using. I know that Hank had to make a custom set of endlinks for his MCS coilovers.
General rule: swaybars should be unloaded from side to side, ie, in a null position, bc they are only intended to be affecting the suspension (increasing spring rate) when cornering. Note: if the swaybar was statically loaded equally on each side it would "in effect" be balanced side to side but it would be continuously statically loaded adding spring rate in normal driving. This tends to transmit road noise and harshness into the car......especially if the bushings ARE NOT FREE FLOATING IN THE D BRACKETS...ie, RS oem swaybar bushings.
Almost all of the posts cite various combinations of sway bar brand (and bushing), and different struts (oem and aftmkt), so it is difficult to narrow in on why some work on one combination and not on another. With different variables it is nearly impossible to have a single answer.
I believe the critical issues are the endlink mounting position on an aftrmkt strut vs oem strut, the relative endlink mounting position of the aftmkt swaybar vs oem swaybar, and the "free floating" bushing common on aftmkt swaybars and the "semi-fixed/ restricted oem bushing (which determinds the orientation of the oem bar).
On my 2016 RS with Mountune black springs, on original front struts and swaybar/bushing, the factory endlinks were preloading the swaybar (downward, too long ). I purchased a used set of WL endlinks from another member, but dont know the pn. If i had changed the front bar to an afftrmkt bar with a "free floating" design bushing any reasonable length endlink, including possibly a stock endlink would have worked bc the bar would have freely rotated to a position allowing the bar to be set with no side to side or overall preload.
The issue with the "semi-fixed" oem bushing is that it creates a preloaded static condition (both sides) using the oem bar with oem struts and lowering springs. Adding an aftrmkt bar with a floating bushing overcomes the semi-fixed bushing issue by increasing the rotation range of the endlink mounting position.
This does not answer which is the correct WL or other brand of endlink to use with which combination of springs, struts, and swaybars...and I suspect it is going to boil down to what part combination you are using. I know that Hank had to make a custom set of endlinks for his MCS coilovers.
Good break down and explanation @lflouie
I would say we can concur that using the OE strut, aftermarket springs, WL front endlinks with OE swaybar are a combo that does work.
Going with aftermarket struts, swaybar, etc is in a state of mystery on what will work (as you said @Hank had to make/engineer his own with his coilovers).
Someone could always take up the cup and create a thread with combos people have been successful with....say like what people have done with rims and other parts....
NOT IT!
![353505]()
I would say we can concur that using the OE strut, aftermarket springs, WL front endlinks with OE swaybar are a combo that does work.
Going with aftermarket struts, swaybar, etc is in a state of mystery on what will work (as you said @Hank had to make/engineer his own with his coilovers).
Someone could always take up the cup and create a thread with combos people have been successful with....say like what people have done with rims and other parts....
NOT IT!
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I just installed the Whiteline 22mm rear sway bar, so here's a few comments on the install; and the road feel on the stiffer setting (23mm = +75% over stock) on an otherwise completely stock car. There were no instructions supplied with the bar and only generic instructions on the Whiteline website. WL Part is BFR78Z. Thanks again to the great people on this forum for tips on the install!
I replaced the bar with the supplied bushings, brackets and lateral locks i.e. retained the stock drop links. There is no preload -- the bar can rotate freely in the bushings (unlike the OEM bar). I did all the install with the car on full droop (stands, wheels off) - I don't see any problem with that as the bar can rotate and so can the ball joints in the links (to a limited extent). Anyway there was no way to get my torque wrench cleanly onto the link nuts (76 lb ft!) with the car on the ground. As there was no supplied grease, and the Whiteline site makes a fuss about their new bushings not needing it, no grease was used. I used blue loctite on all the torqued fasteners i.e. I reused them (the workshop manual says to replace the link nuts, probably because they come with thread-lock pre-applied).
The lateral locks won't hit the bracket as the bar rotates provided they are installed 1-2 mm from the bushing (not 3-4 mm as Whiteline recommend), and on the inner side of each bushing (as per the OEM bar). There is a convenient slot in the support bracket that allows the lateral lock to rotate (through 360 degrees -- yes I checked) without hitting anything. Its close, so this will need checking after a few miles. See the picture - remember that the lateral lock can move 1-2mm to the left before the lateral lock on the other side stops the bar. It should still clear the slot in the bracket...
![353605]()
If you are an occasional DIY guy like me: A few additional tools you might need beyond the basics: T40 torx, 3mm hex (WL supply a key), 6mm ball head hex (to keep the ball joint from rotating as you turn the link nut), 18mm ratcheting spanner, 13mm deep socket.
![353606]()
First drive with the bar I did a U-turn with power on as usual and the inside wheel kicked off the ground and the car 'skipped' sideways - not good. So I have set the bar to the softer setting = 22mm +46% over stock. Its been raining here since so I'm yet to retest. Looking forward to that.
Why do this? Mainly because of the discussion here, and I did this mod on my previous car (WRX) and it was a big improvement, and WL had a 40% discount deal, so why not! Easy reversible DIY mod also.
I replaced the bar with the supplied bushings, brackets and lateral locks i.e. retained the stock drop links. There is no preload -- the bar can rotate freely in the bushings (unlike the OEM bar). I did all the install with the car on full droop (stands, wheels off) - I don't see any problem with that as the bar can rotate and so can the ball joints in the links (to a limited extent). Anyway there was no way to get my torque wrench cleanly onto the link nuts (76 lb ft!) with the car on the ground. As there was no supplied grease, and the Whiteline site makes a fuss about their new bushings not needing it, no grease was used. I used blue loctite on all the torqued fasteners i.e. I reused them (the workshop manual says to replace the link nuts, probably because they come with thread-lock pre-applied).
The lateral locks won't hit the bracket as the bar rotates provided they are installed 1-2 mm from the bushing (not 3-4 mm as Whiteline recommend), and on the inner side of each bushing (as per the OEM bar). There is a convenient slot in the support bracket that allows the lateral lock to rotate (through 360 degrees -- yes I checked) without hitting anything. Its close, so this will need checking after a few miles. See the picture - remember that the lateral lock can move 1-2mm to the left before the lateral lock on the other side stops the bar. It should still clear the slot in the bracket...
If you are an occasional DIY guy like me: A few additional tools you might need beyond the basics: T40 torx, 3mm hex (WL supply a key), 6mm ball head hex (to keep the ball joint from rotating as you turn the link nut), 18mm ratcheting spanner, 13mm deep socket.
First drive with the bar I did a U-turn with power on as usual and the inside wheel kicked off the ground and the car 'skipped' sideways - not good. So I have set the bar to the softer setting = 22mm +46% over stock. Its been raining here since so I'm yet to retest. Looking forward to that.
Why do this? Mainly because of the discussion here, and I did this mod on my previous car (WRX) and it was a big improvement, and WL had a 40% discount deal, so why not! Easy reversible DIY mod also.
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but you were just busting a U-turn...no biggy if the inside wheel comes off the ground...right?
what's the verdict on normal turns...curvy roads?
i'll be fitting an eibach rear sway bar this month. thanks for your post.
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big Jim, yes I agree, lifting a wheel is not a big issue. However in this case I was worried by the 'skip' sideways - it felt like rear of the car 'hopped' about 20cm in one step, and that was not usual i.e. was due to the RSB. Today I repeated the same test at the same U-turn point with the RSB set to the normal setting (22mm = +46%). The inner wheel did not lift and the car 'hopped' but at a much higher frequency - I mean multiple little steps rather than one big step sideways. This is a rather stupid test (I mean, who cares?) but it does show the effect of the RSB.
I drove through a few nearby twisties also - unfortunately still wet here so I couldn't get full traction to test the limits. The effect is subtle - getting on the power as usual, after initial turn in, had more effect on the rotation of the car. But more driving on familiar roads at higher speed is needed to come to a conclusion. I also want to check for the dreaded lift-off snap oversteer on a suitably wide, quiet, wet corner.
Certainly no ill effects. No noises, no change to ride feel, no sudden shifts in weight when turning in or changing direction.
I recommend checking the lateral locks after the first drive. I had to reset mine to 1mm off the bushing as they were both touching the bushing.
This is for all - I know WL stated the same that @Alpha Dog took in that these bushings did not need grease. However being old school I probably went overboard and lightly greased the poly bushings anyway (probably use a torque wrench more than I should as well).
Force of habit maybe and don't see the harm in it unless someone can give a good reasoning as to why one shouldn't other than the manufacture saying they don't need it.
In
Regarding the percentage increase over stock, those numbers are higher than I recall, by approx 20 - 30%. Were these quoted by WL....just curious?
Remember that the percentage of increase is dependant on the rotational deflection. If they are at max deflection (whatever distance that might be) then they will reach the max increase %, but in most applications/situations the deflection is far less and therefore the percentage is less. If you'll look the WL Swaybar vendor announcement on this site, you'll see stiffness percentage ratings at various deflection points.
In my experience snap oversteer (like lifting an inside wheel) is caused by 2 primary factors 1) the effective wheel spring rate ( actual spring rating plus sway bar spring rate at a deflection distance/ point) and 2) the damping. Too stiff of a spring rate (sway bar and or springs) can certainly create this phenomenon, but so can overly stiff rebound or compression damping ...not allowing the inside tire/wheel to extend fast enough to retain road contact or in the case of compression damping, exceeding the lateral grip of the outside tire. Since the RS has notoriously stiff rebound in the sport mode this can be causing the lifting in your artificial test model. Additionally the drive modes allow different "slippage" rates in the rear diff and the stability control sensitivity and may be a contributing factor.
Depending on the year and production date of your RS, you may have the older (orig) rear struts which had stiffer damping than the Rev 1 struts. I know when I went to rev 1 they were softer and needed the stiffest setting.
Look frwd to your assessment of the new bar.
With regards to the skipping, did you fully disable the traction control when you did this test? What suspension setting were you using (normal or sport)?
Regarding the percentage increase over stock, those numbers are higher than I recall, by approx 20 - 30%. Were these quoted by WL....just curious?
Remember that the percentage of increase is dependant on the rotational deflection. If they are at max deflection (whatever distance that might be) then they will reach the max increase %, but in most applications/situations the deflection is far less and therefore the percentage is less. If you'll look the WL Swaybar vendor announcement on this site, you'll see stiffness percentage ratings at various deflection points.
In my experience snap oversteer (like lifting an inside wheel) is caused by 2 primary factors 1) the effective wheel spring rate ( actual spring rating plus sway bar spring rate at a deflection distance/ point) and 2) the damping. Too stiff of a spring rate (sway bar and or springs) can certainly create this phenomenon, but so can overly stiff rebound or compression damping ...not allowing the inside tire/wheel to extend fast enough to retain road contact or in the case of compression damping, exceeding the lateral grip of the outside tire. Since the RS has notoriously stiff rebound in the sport mode this can be causing the lifting in your artificial test model. Additionally the drive modes allow different "slippage" rates in the rear diff and the stability control sensitivity and may be a contributing factor.
Depending on the year and production date of your RS, you may have the older (orig) rear struts which had stiffer damping than the Rev 1 struts. I know when I went to rev 1 they were softer and needed the stiffest setting.
Look frwd to your assessment of the new bar.
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The U-turn test was done with the car in Sport driving mode = normal suspension & traction control normal. In my experience attempting a quick U-turn in Normal drive mode will trigger engine torque reduction, while Sport drive mode doesn't limit engine torque as much. Limiting engine torque is a function of traction control, but I cannot explain why the TC behaviour is different in Sport vs Normal drive mode because TC is 'normal' for both drive modes.
The sway bar torsional stiffness is proportional to the diameter of the bar to the 4th power. For a 22mm versus the stock 20mm that's an increase of 46%. All else being equal the force applied at a given deflection will also increase by 46%. WL provide a table with the 4th power values calculated - attached. According to that WL doc, their 2 hole adjustable bar is effectively 22m on the longer setting (should be the same arm length as OEM) and 23mm on the shorter setting (shorter arm length than OEM).
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