Superpro 24mm front swaybar - Installation & initial reviewStarting suspension setup. As a reminder, this was the starting point to which I added the new front swaybar:-
Stock height
Stock wheels
Bridgestone RE003 tyres
WHITELINE Adj Rear Swaybar 22mm (middle setting)
WHITELINE end links (lock nuts added) OEM end links
2009-model rear struts (thicker springs than 2008)
rebuilt upper ball joints on rear control arms
Superpro upper and lower subframe voidfillers (rear)
Superpro replacement front lower control arms (2014+ WRX) for more caster
Pedders front swaybar bushes on stock 21mm front swaybar.
With all of the above I wasn't happy with the way the front end would lean over and get nervous during high-speed sweeping corners.
Superpro 24mm front swaybar - what's in the packet?The swaybar, some poly bushes, some silicone grease and some destructions.


Despite a very thick coating and being tripled-bagged for shipping (including an inside bag made of bubble wrap), clearly this one had copped a beating at some point as shown in some damage to the powder coat:-
InstallationOverall this is pretty easy from a DIY point of view. It took me a few hours one evening during the week plodding along.
Please note that YOU are responsible for checking this again after 1000kms (including bolt torque). The Gregory's manual notes repeatedly that "the manufacturer recommends using new self-locking mounting nuts when installing the stabiliser bar links"1. Get the front of the car up on wheel ramps. Installing swaybars with the suspension sitting normally is very important. Also, take off the plastic under-tray.
2. Remove this Crossmember Support Plate. A breaker bar and some WD40 made the job easier.

3. Undo the swaybar ends of the end links. An allen key is essential. a ratcheting ring spanner makes this a lot easier.
4. Undo the bolts on the bracket bushes and remove the old swaybar. 
Note the Pedders bushes and brackets on mine. The width difference meant my Pedders brackets wouldn't work with the stock-width Superpro bushes.

Lucky for me, my wife's stock SH was parked right there and it turned out to be a good time to upgrade her front suspension with Pedders bushes and brackets as a thoughtful surprise. There was plenty of silicone grease in the supplied sachet to do both and plenty more.
The bushes are accessible/replaceable by only removing the under-tray, which is handy.
This got me a stock set of bush brackets. Great success.
5. Bolt the end links onto the new swaybar and let it hang thereInstall loosely at first.


Before you send letters pointing out that I stuffed up by bolting the driver's side on the back hole and the passenger's side on the front hole -
I did this deliberately to get a sense of a genuine 24mm front swaybar (rather than the equivalent of a bit thinner on the outer holes or the equivalent of a bit thicker on the inner holes).
According to a Flatirons Tuning youtube video, you can do this so get an interim/middle setting on swaybars with multiple hole option. Since nothing incorrect would be allowed on the internet, it is a
handling fact.
The stock end links are pretty strong-looking and flexible as to how they sit, so it also seems workable to me in practice.
6. Grease up the supplied bushes and install them on the barInside and outside surfaces. Splits facing forward seems to be how my two examples came off, so I repeated that with re-installation.
7. Clean the OEM bush brackets and install them over the bushes and on the barInstall loosely at first.
Wipe off excess grease that eases through on tightening up.


The above photos are shown after bolt tightening. I'm not 100% happy with the bush distortion shown. It seems to be a result of the bend in the bar occurring quite close to the edge of the bush. Perhaps the bar wasn't 100% central on initial installation either.
Something to check when I next stick my head under the car (to re-check bolts torque) and in general - eg for early bush wear/cracking.
8. Reinstall the Crossmember Support PlateInstall loosely at first.
9. Tighten all bolts per torque specificationsAccording to the Gregory's manual:-
End Links 38Nm / 28 ft lb
Bush Brackets 40Nm / 29.5 ft lb
Crossmember Support Plate 60Nm / 44.3 ft lb
I used Loctite when re-assembling. The lubrication (while wet) might have affected the apparent torque according to the torque wrench.
10. Re-install plastic under tray.(self explanatory)
Handling after In lower-speed tight corners the turn-in is noticeably better, but perhaps with a tiny bit more understeer.
For rapid left-right-left through traffic calming the front of the car is much more decisive.
For high speed sweeping bends the front stays much more level and stays on the intended line rather than understeering. It's much more confidence-inspiring.
Overall the handling envelope seems to be bigger, with the shifting balance from oversteer to understeer in certain circumstances being eclipsed by that overall better handling.
All testing so far has been in the dry.