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Progress Anti-Sway Bar = New RSB option?

24K views 46 replies 22 participants last post by  TalonTsi90 
#1 ·
Since removing my JBR RSB due to excessive ride harshness, I've been searching for a replacement to tighten up the rear that's not so stiff. I had recently noticed that the Corksport, JBR, and Ultra Racing RSB's are the same for the Mazda 3 and 6. A clue. I started browsing some 3 forums and saw a lot of positive reviews for this bar from Progress:


Progress Technology: Anti-roll bars, sport springs, coil-overs, camber kits and more since 1995!

It's apparently almost as stiff as the Corksport bar, but doesn't have the CS bar's dreaded clunk (which mz3 owners are reporting as well). I actually like that it has beefier mounting brackets that are not as obnoxious as the billet pieces from JBR and CS. Those JBR brackets were a pain to install and probably added to the harshness of the ride.

Anyway, I ended up ordering the Progress bar for $145.33 shipped and am very happy about it. They look to be out of stock at several places, so who knows when it will arrive. Just wanted to get a post up here for anyone else that wants to take a chance (which looks to be a slam dunk) on this bar in the meantime, as it will probably be a few months before I get it installed.
 
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#5 ·
Post-Install Update

Abstract: I freakin' love it. Perfect in all aspects.

Background: The body roll and understeer in the Mz6 is excessive to say the least. Tanabe NF210 springs helped a bit, but I really wanted to lock up the rear with a stiffer RSB to help the car through corners without adding harshness to the ride.

I kept reading about how people with the Corksport RSB get a bothersome clunking noise and some have reported it rubbing in areas. Did not want that. As much as I also didn't want a giant overkill bar, I picked up a used JBR RSB for cheap and gave it a shot. The car cornered absolutely flat, but the rear end was far too stiff for city roads. Out came the JBR RSB and in went the stock bar, sacrificing handling for comfort as any pansy would do.

***Special note: the ride was still fairly stiff with the OE RSB -- presumably because I severely overtorqued the brackets (and the bushings are not lubricated). The service manual calls for the nuts to be tightened to 16-19 ft-lbs to just barely compress the rubber bushings. I cranked them down to probably 50-60 ft-lbs. When I went to remove the OE bar, it was so bound up in the bushings that I couldn't rotate it even with the nuts loose. I had done the same thing with the JBR RSB. Installer beware.

Procedure: I found the Progress RSB (see first post) and went about installing it this weekend.

1. I measured the two bars:
OE: 17.15mm
Progress: 22.40mm​
This was interesting since the Progress website lists the OE bar at 18mm. It's super wimpy either way. The Progress bar is a monster comparatively. It felt very strong and the welds/brackets looked good. (It's a steel bar woo!)

2. Since this bar isn't marketed for the 6, I went ahead and overlaid it with the OE bar to make sure the dimensions were comparable. We good.



3. Compared the brackets. Digging the slotted holes on the Progress brackets. Made install much easier.


Note: I despised the giant billet brackets that came with the JBR RSB. It was nearly impossible to get a tool in there to tighten the nuts. That's one of the reasons that I overtorqued them -- if they had come loose, I probably would have just put the car into a lake rather than deal with them again.

4. Compared the bracket placement. Everything looks good--into the car with you!



5. Now we get to the part where I overtorque the mounting brackets again NOT SO FAST. These brackets have stiffer polyurethane bushings that don't need to be compressed. I was able to tighten the brackets all the way down without fear of binding the bushings. I believe ecstatic is the word. I cranked the nuts down, locking the brackets onto the subframe, and could still freely rotate the bar. This was not the case with the OE or JBR bars. I would also not even consider describing it as "loose" since the stiff poly bushings don't compress like the rubber ones. They act more like a lubed up plastic sleeve than anything.

6. Clearance check -- all is well. I should note that I slid the brackets up/towards the front of the car before tightening the nuts to maximize the clearance for the ends to rotate. It looked like it would have been fine if mounted all the we down/towards the rear, though. No concerns about clunking here.

Results: Perfection. The car rides better than I can remember. The bar is free to rotate in the poly bushings as the suspension travels over bumps, so no more jarring railroad crossings. The body roll is greatly diminished. The reduction in understeer is already comparable with the JBR tank barrel on the soft setting, but the firm setting may be even more fun. I installed it on the soft setting to start and will keep it there until I get my Koni FSD's installed & broken in.

I think that's all I have to share on this bar. It's cheap, well made, and functionally perfect for me. Very happy customer here.
 
#16 ·
Abstract: I freakin' love it. Perfect in all aspects.

Background: The body roll and understeer in the Mz6 is excessive to say the least. Tanabe NF210 springs helped a bit, but I really wanted to lock up the rear with a stiffer RSB to help the car through corners without adding harshness to the ride.

I kept reading about how people with the Corksport RSB get a bothersome clunking noise and some have reported it rubbing in areas. Did not want that. As much as I also didn't want a giant overkill bar, I picked up a used JBR RSB for cheap and gave it a shot. The car cornered absolutely flat, but the rear end was far too stiff for city roads. Out came the JBR RSB and in went the stock bar, sacrificing handling for comfort as any pansy would do.

***Special note: the ride was still fairly stiff with the OE RSB -- presumably because I severely overtorqued the brackets (and the bushings are not lubricated). The service manual calls for the nuts to be tightened to 16-19 ft-lbs to just barely compress the rubber bushings. I cranked them down to probably 50-60 ft-lbs. When I went to remove the OE bar, it was so bound up in the bushings that I couldn't rotate it even with the nuts loose. I had done the same thing with the JBR RSB. Installer beware.

Procedure: I found the Progress RSB (see first post) and went about installing it this weekend.

1. I measured the two bars:
OE: 17.15mm
Progress: 22.40mm​
This was interesting since the Progress website lists the OE bar at 18mm. It's super wimpy either way. The Progress bar is a monster comparatively. It felt very strong and the welds/brackets looked good. (It's a steel bar woo!)

2. Since this bar isn't marketed for the 6, I went ahead and overlaid it with the OE bar to make sure the dimensions were comparable. We good.



3. Compared the brackets. Digging the slotted holes on the Progress brackets. Made install much easier.


Note: I despised the giant billet brackets that came with the JBR RSB. It was nearly impossible to get a tool in there to tighten the nuts. That's one of the reasons that I overtorqued them -- if they had come loose, I probably would have just put the car into a lake rather than deal with them again.

4. Compared the bracket placement. Everything looks good--into the car with you!



5. Now we get to the part where I overtorque the mounting brackets again NOT SO FAST. These brackets have stiffer polyurethane bushings that don't need to be compressed. I was able to tighten the brackets all the way down without fear of binding the bushings. I believe ecstatic is the word. I cranked the nuts down, locking the brackets onto the subframe, and could still freely rotate the bar. This was not the case with the OE or JBR bars. I would also not even consider describing it as "loose" since the stiff poly bushings don't compress like the rubber ones. They act more like a lubed up plastic sleeve than anything.

6. Clearance check -- all is well. I should note that I slid the brackets up/towards the front of the car before tightening the nuts to maximize the clearance for the ends to rotate. It looked like it would have been fine if mounted all the we down/towards the rear, though. No concerns about clunking here.

Results: Perfection. The car rides better than I can remember. The bar is free to rotate in the poly bushings as the suspension travels over bumps, so no more jarring railroad crossings. The body roll is greatly diminished. The reduction in understeer is already comparable with the JBR tank barrel on the soft setting, but the firm setting may be even more fun. I installed it on the soft setting to start and will keep it there until I get my Koni FSD's installed & broken in.

I think that's all I have to share on this bar. It's cheap, well made, and functionally perfect for me. Very happy customer here.
Great writeup!
 
#6 ·
Good stuff. I hope it's a nice quality poly bushing otherwise it may loosen up and make noise down the road. Might need to get me one of these soon!
 
#10 ·
I should hope so. The Mz3 guys love this company and their product. Haven't seen them say anything about noise from the bushings [yet]. It came with synthetic grease...so that's good?

How much of a PITA is this? It was pretty straight forward on my 2010 Speed3. Thanks.
It's kind of a bear since it mounts on top of the subframe. It would have been a lot easier if I had a 14mm deep well 1/4" drive socket. My 1/4" drive deep sockets only go up to 13mm, so I had to do everything with a 3/8" drive wrench and it is very difficult to fit a long wrench in there.

You have to lower the rear subframe
You don't have to lower the subframe for a non-JBR RSB, but it's really simple and makes the removal/install a lot easier. I did it with this bar just to give myself more room to turn the longer-than-necessary wrench.

And as scary as lowering the subframe sounds, it's a matter of loosening four nuts (and removing two if you want even more room to work). It won't fall out of the car or screw up the alignment.
 
#7 ·
How much of a PITA is this? It was pretty straight forward on my 2010 Speed3. Thanks.
 
#18 ·
All good here. I've been lucky enough to take a few mountain trips recently and really push it. I'm hoping to get under the car and change the RSB to the stiff setting before hitting the mountains again this weekend.

I have a few questions:
  • You really feel that this current generation Mazda6 has a massive amount of understeer?
  • Have you taken the car to a parking lot for a skidpad test to see if it still understeers, oversteers or is neutral?
  • Did you lube the poly bushings before your install?

The 7th generation Honda Accords came with a 14mm rear swaybar. A cheap upgrade was ordering the Acura 17mm rear bar and brackets for less than $50.00! That reduced the understeer in 4 cylinder substantially; not neutral, but very little understeer. It still wasn't enough for 6 cylinder cars as the V6 Accord was about 200lbs heavier, all on the nose.

I may have not pushed my Mazda6 hard into corners yet, but quick jabs of the wheel don't seem to induce detectable understeer. I find the overall suspension about perfect, but again I haven't pushed it hard into corners yet.
I feel the understeer when I push it into a corner. Haven't been to a parking lot or anything...I'm not sure how to go about that test, but I'd be happy to go slide it around and collect whatever data you would be looking for. And yes, the poly bushings came with some synthetic lube that I applied. 6 months of abuse and no creaking bushings!

I see that you posted this back in August -- have you had a chance to push the car into some corners yet? I was like you and felt like the suspension was very responsive until I really pushed it and couldn't get the car to rotate. The stock setup is wonderful on long sweeping turns, but you feel how front heavy the car is in tight corners.
 
#20 ·
I just ordered one from THMotorsports. I agree that the 6 in stock form has a TON of understeer push at lower speeds. Not sure if this is due to alignment settings or swaybar balance. Will report back once I install it.

On that note, has anyone tried putting an auto-x or track alignment on the 6?
 
#23 ·
Hard to say exactly as I made two changes at the same time. I went from this:

Springs: Tanabe
Shocks: Koni FSD
RSB: Progress Soft

to this:

Springs: OE
Shocks: Koni FSD
RSB: Progress Stiff

and the car gets through tight corners MUCH better. I can't tell how much of the flat cornering on OE springs can be attributed to the FSD's or the RSB, but definitely noticed the difference in how tight the car turns, which is due to the RSB. I fully endorse the stiff setting.
 
#25 ·
I installed this bar on my M6 last weekend. Absolutely fantastic. It used to be a chore to drive this car through curvy roads, now it is a pleasure.

I choose the looser of the two settings. Now, while coasting (no throttle/braking) around a bend, the car is completely neutral with no signs of understeer or oversteer. The back tires actually start to make some noise, where before only the front tires would squeel as it understeered.

At low/medium speed turns when I dig into the throttle, the fwd whips the front end around the turn and doesn't induce any understeer. I have yet to hit the limit in any high speed turns/sweepers so I cannot comment when traveling faster than say 40mph around a bend. However, I have no reason to believe the car would behave any differently.

In fact, the bar (and some yellow-stuff pads) made such a difference that I am debating if I even need summer sport tires or if I should keep running all-seasons. I like the ability to drive in light snow up in the mountains.
 
#39 ·
Nice setup! Ive got the progress bar on the loose setting and yellowstuff pads aswell. Have you had an alignment recently? The reason I ask is my car is still not quite neutral off throttle, and tends to push slightly at the limit. Just curious about that or any other differences from stock?
 
#26 ·
Thread revival here. After doing lots of research on the "best" RSB for my needs, I found Donkey's thread here about a month ago. Sign me up as another happy user of the Progress RSB. So far only on the softer setting, but the rear is really planted in daily driving (hello on-ramps) compared to before. No noise or harshness to report... Steering is very direct now! No more "boat rolling" when I steer.
 
#28 ·
I recently installed the Progress RSB, order directly from Progress just order the one labeled for Mazda 3 as they are the same, and I LOVE it. Car turns so much sharper, and no clunking or noises.
 
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#30 ·
I was hoping they were since so much else on the car is the same.
 
#34 ·
After reading all these positive comments I just ordered mine off the link and it was the last one! Sorry future posters lol. I'm excited to see how this will affect the car while also having the tanabe strut bar installed. Also can anyone with the progress RSB installed let me know if they kept the stock links and if not which ones they went with?
 
#35 ·
I replaced the end-links with Moog ones from RockAuto that are way thicker than the stock ones (keep in mind left rear and right rear are slightly different, so it's not just a matter of ordering two).
IF you're not going to use the stiffer setting you might be able to stay with the stock ones, but I push my car hard and didn't want to snap one.

How difficult was it to get out without dropping the subframe? Curious. As dropping it seems easy enough.
I'm not sure if it's possible to do without lowering the subframe a couple inches, it's a tight spot. Honestly it wasn't too bad lowering the subframe, 4 bolts, and will make the whole process MUCH easier.
 
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