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Antiroll Bar Info

Antiroll Bars (also called Anti-Sway, Sway or Stabilizer bars) - If you feel the body roll in the corners is too much, you can upgrade the anti-roll bars. In reality the R1 suspension is a very good street/race course compromise. Most alterations will make it ride even harsher. Some people have suffered antiroll bar mount failures during extended track use. There are beefed up after-market mounts available from Racing Beat, Mostly Mazda, Crookedwillow Racing and others. If you go to an aftermarket front antiroll bar I highly recommend you beef up the mount too. It's also important to make sure the antiroll bar end links (connect bar to the suspension) are as vertical as possible. If they aren't they will stress the antiroll bar mount horizontally and eventually cause mount cracking (another reason to upgrade the mount).

The stock front antiroll bar with upgraded RB mount (white) and Energy Suspension bushings. See the Antiroll bar bushing upgrade how-to here.


Front Antiroll Bar Information

The following is from Kevin Kelleher

Pettit Trackpro sway bars

For the 3rd gen sway bars (anti-roll bars), stiffness will be based mostly on (Do^4 - Di^4).  Based on this factor, I rated the front bars, relative to stock. (Cirian's site has some misinformation on bar stiffness.)
Size --- Wall --- (% stiff increase) --- Vendors
1.25" --- solid --- (114%) --- ST
1.31  --- .188 --- (92) --- RB
1.25  --- .250 --- (86) --- M2, TP
1.25  --- .188 --- (62) --- M2, TP, EB, PF?
1.13  --- solid --- (40) --- AD, Pettit
1.25  --- .125 --- (26) --- M2,TP
1.25  --- .095 --- (4) --- TP
1.13  --- .150 --- (0) --- Stock Front (but with poly bushings for stiff comparison, 28.6mm)
0.68  --- hollow - (0) --- Stock Rear 93 only (17.3mm)

0.63  --- hollow - (0) --- Stock Rear 94, 95 (15.9mm)

Rear Antiroll Bar

Rear stock bar is hollow, and larger (17.3mm, 0.68 inch) in 93 only, all models. 94 and 95 have a smaller 15.9mm, 0.63 inch rear bar.  Only 19mm upgrade is available (forget the .88" solid Addco bar). Compared to the big stock 93, the solid 19mm will be about 50-60% stiffer at stock arm length. I tested the EIB hollow rear at 30% stiffer at 'long' hole, and 50% stiffer at 'short' hole.  RB sells a separate 19mm hollow rear bar, looks to be non adjustable.
Notes: (confirm current prices)
TP=Tri-point, adjustable-5 holes, @mazda-comp?, heim links, $470 front
ST=Suspension Techniques, @mazdatrix, $272 set, adj solid rear
RB=Racing Beat, $377 fr (Brad Barber noted 2 failures)
M2=Mostly Mazda, adj-3 holes, heim links, $385 fr
PF=Peter Farrel, $350 set, adj solid? rear
Addco, $175 front
EB=Eibach, $277 set, adj hollow rear
1) Actual stiffness change vs stock will be more than listed due to conversion to stiffer pivot bushings (and end links in some cases) vs stock parts
2) RB, TP, and M2 have 3 piece splined design. Stiffness listed assumes 'stock' arm length, although this may be between adj-holes.
3) TP has optional solid pivots that effectively shorten the arms, making it stiffer.
4) Eibach is changing design, solid?, so current size may change. I have this set. Rear fit needed a lot of work. Front is VERY stiff, nice at track but degrades street ride a bit.
5) With bigger front bar, support bracket bracing is needed. Check RB, TP, CWC (raises bar for more ground clearance), and M2. I like M2's 1-piece support assembly for $250, stout mounts with RB type bracing.
6) If you value comfort, just add an Addco front bar. Solid version of stock 28.6mm hollow bar, 40% stiffer, and only upgrade that uses rubber pivot bushings (oem) for best ride comfort. Should work well with stock 93 rear bar, maybe push a little with 94+ rear bar. The Addco rear bar is 22mm, solid, and useless to all.
Kevin Kelleher

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