SilverHoss

Hi all,

The rear sway bar on my 2011GT is 24mm, which is a bit big. Wanting to up-size the front one a bit to better balance the handling and reduce some body roll. Any recommendations on a front bar/size to match the 24mm rear one?
I'm thinking adjustable 36mm?

thanx lotz

steel pony

I'll chime in here and give you what information i have uncovered. Anybody welcome to correct me if i'm wrong.

Yes, the rear sway bar is 24mm, the front is 34.66mm i think. Both are solid steel. Everything that i have found aftermarket is a 36mm so not being an expert, not sure how much you gain in a 1.34mm increase

You could upgrade to tubulars, but it may just be splitting hairs in the handling vs. weight loss the major difference being the bushings.
If you intend on tracking the car, then yes an adjustable would be the way to go. I DD mine and look for any opportunity to run it thru the twistys, handles just fine being lowered, traction control off and steering set on sport setting.

If you decide on an adjustable i'd say Hotchkis or Eibach

SilverHoss

Yeah, I'm thinking of going with an Eibach 36mm one.
I had a Hotchkis on my '08GT, but it was brutal...their bar is 38mm and hell on bumpy roads.
I just mainly want to balance the front with what the rear has. Not sure why Ford has increased the rear bar size on the S197 in recent years? My old '08 came I think with a 19mm rear and 34mm front, not sure why they have now inceased the rear to 24mm?
Anybody else have any input on this?

Black Fire

Its my understanding that the larger rear bar lets the car rotate around the corners easier.

SilverHoss

I know. But too much rear bar can make the car tail-happy which can make the car "twitchy" in the corners and then it can even get beyond your control if you're not careful.
I think Sam Strano said he went down to a 22mm rear bar on his.
I would rather go up in size on the front than downsize the rear myself. I just don't know what size to go up to in order to balance with the rear.

157dB

The mustang magazines have touched base on
why the increase in sway bar sizes for the 2012-13 models.
Car and driver has as well. They magazines have really
given up the details of the improvements to the Mustangs
suspension. Real good reading.

05-09 S197
GT 20mm rear sway, 34mm front
V6 Pony 18mm rear sway 31.5mm front sway
V6 no rear and 31.5mm front sway

05-09 S197
The front sway bar is hollow and lighter.
The added surface area inside makes it as
stiff as a larger heavier solid sway bar.
You cannot go on O.D. size when comparing
solid and hollow sway bars.

https://mustangforums.com/forum/v6-s...-question.html

Norm Peterson

Tubular bars are somewhat less stiff than solid bars of the same shape and outside diameter. It's an [OutsideDiameter]^4 - [InsideDiameter]^4 thing.

The 34mm tubular OE bar on the GT has a wall thickness of about 15% of the outside diameter. A solid bar of the same shape and stiffness would be about 31.7 mm outside diameter.


FWIW, rear bars aren't nearly as effective at reducing roll as the front bar is, so it's best to consider using/swapping them only for balancing or re-balancing the handling. Take any reduction in roll as a pleasant side effect.

Front and rear spring rates also have some effect on handling balance, as stiffer than OE springs or a different mix of OE springs from year to year will also affect the handling balance. IOW, the combination of bar diameters and tubular vs solid that works nicely for, say, a 2008 GT may not work as well for the same driver in a 2011 or later.


Norm

Black Fire

Yeah I had a 35/22 combo from Stano on my F-body.
Along with his springs and Koni S/A's the car was awesome.

Sam Strano

My front bar is 35mm (34.9) which adds stiffness in itself... but also I use a 6.25mm wall tubing where stock is 4.4mm. My bar is a good bit stiffer (and adjustable, and comes with much beefier mounts than Eibach too).

As for the rear bar. There are reasons for a little less rear bar. Though I've made a small change. Went from a 22mm .188" wall, to a 25mm, but a .156" wall tube. Found nobody was using full soft on the rear, or full stiff on the front. I wanted all positions to be in play if possible, and since it was clear that two of them, one each on each bar, were almost never used, I adapted.

So what I do now is a 35/25 combo. Both hollow, front bar a pretty heavy tubing, rear bar a very light tubing.

As for not wanting to go smaller or lighter on the back, why not? If you think that bigger is always better that can lead to trouble. More is not always better. The right amount is better. Balance is better.