RB Swaybar
Originally Posted by ULLLOSE
Yes 5th and 6th place ran the RB front bar... They ere 1st and 2nd the first day.
Thanks for reminding me...
All I want is one for Christmas is one shot at the South course with a smaller front bar...
GAH! What misinformation is spreading here...
-this thread is specifically about running in B-stock, and assumes competitive racing on autox courses on r-compound tires, maybe with aftermarket shocks.
-you can't run a rear bar in BS
-the RB bar is about 208% stiffer than stock. I think the MS bar is something like 30% stiffer.
-sway bars add to the spring rate when the suspension components are in opposite movement. When the left a-arms move up, and the right a-arms move down, the sway bar is adding to the spring rate on the compressed side. This is something of an over-simplification, but its good enough.
-in transitional situations, slaloms and the like, the sway bar helps
-in sweepers, the swaybar couples the wheels together, which can unload or upset the tires when a bumb is encountered on one side. Once this happens, some traction can be lost.
-the fact that the guys on the RB bar were 1-2 after day one of Nat'l should say that the RB is not uncompetitive. Is it the best setup? That's still debatable, as we've only run these cars for 1 year of solo2.
-most handling problems can be solved by changing your driving style. The RB front bar requires less trailbraking and much more careful speed control when entering turns to avoid tragic push.
-a bigger front bar will increase the tendency of the car to understeer, especially in sweepers.
-all parts of the setup must be looked at in whole. The RB bar, in combinations with tire pressures, shock valving, and alignment may result in a very fast setup. Or not.
-this thread is specifically about running in B-stock, and assumes competitive racing on autox courses on r-compound tires, maybe with aftermarket shocks.
-you can't run a rear bar in BS
-the RB bar is about 208% stiffer than stock. I think the MS bar is something like 30% stiffer.
-sway bars add to the spring rate when the suspension components are in opposite movement. When the left a-arms move up, and the right a-arms move down, the sway bar is adding to the spring rate on the compressed side. This is something of an over-simplification, but its good enough.
-in transitional situations, slaloms and the like, the sway bar helps
-in sweepers, the swaybar couples the wheels together, which can unload or upset the tires when a bumb is encountered on one side. Once this happens, some traction can be lost.
-the fact that the guys on the RB bar were 1-2 after day one of Nat'l should say that the RB is not uncompetitive. Is it the best setup? That's still debatable, as we've only run these cars for 1 year of solo2.
-most handling problems can be solved by changing your driving style. The RB front bar requires less trailbraking and much more careful speed control when entering turns to avoid tragic push.
-a bigger front bar will increase the tendency of the car to understeer, especially in sweepers.
-all parts of the setup must be looked at in whole. The RB bar, in combinations with tire pressures, shock valving, and alignment may result in a very fast setup. Or not.
Surprises me that the RB bar would be that fast at nationals. All I can relate is my experience with this setup. Again, this only applies with the konis. On stock shocks I liked the bar.
With the RB bar installed I couldn't get on the gas exiting turns until way later than I liked. The bar requires massive trailbraking to set up a line through a turn unless you want to give up both turn entry and exit.
On slaloms and transitions, the inability to rotate the car made it very difficult to stay ahead and execute good late apexes. Too much gas and the car would push beyond the apex getting you behind for the next one.
On the stock bar (with additional hole drilled) the car is loose but fast. Coming from a miata, this surprised me. I was able to be much more aggressive without the rear end coming around. A miata set up this way would be spin city, but not the RX-8.
Overall, I really can't imagine a course where I would want to run this bar. I hate to say it, but the fact for me that the car is no fun to drive with it installed is 2 strikes against it regardless of times. A car that refuses to rotate is no fun.
With the RB bar installed I couldn't get on the gas exiting turns until way later than I liked. The bar requires massive trailbraking to set up a line through a turn unless you want to give up both turn entry and exit.
On slaloms and transitions, the inability to rotate the car made it very difficult to stay ahead and execute good late apexes. Too much gas and the car would push beyond the apex getting you behind for the next one.
On the stock bar (with additional hole drilled) the car is loose but fast. Coming from a miata, this surprised me. I was able to be much more aggressive without the rear end coming around. A miata set up this way would be spin city, but not the RX-8.
Overall, I really can't imagine a course where I would want to run this bar. I hate to say it, but the fact for me that the car is no fun to drive with it installed is 2 strikes against it regardless of times. A car that refuses to rotate is no fun.
Originally Posted by Sparky
The bar requires massive trailbraking to set up a line through a turn unless you want to give up both turn entry and exit.
Originally Posted by Sparky
On the stock bar (with additional hole drilled) the car is loose but fast. Coming from a miata, this surprised me. I was able to be much more aggressive without the rear end coming around. A miata set up this way would be spin city, but not the RX-8.
Originally Posted by Sparky
Overall, I really can't imagine a course where I would want to run this bar. I hate to say it, but the fact for me that the car is no fun to drive with it installed is 2 strikes against it regardless of times. A car that refuses to rotate is no fun. 

Originally Posted by tuj
Exact opposite of what I found. When I switched to the RB bar, I couldn't trail brake at all. I know at least a couple other people have said the same thing.
And yes, I understand the difference between loose and fast. That's why I said loose AND fast.
The car is loose off the gas and neutral under power because I like it that way. Yes I could get mild understeer if I wanted but I don't because this car doesn't need it to keep the nose pointed in the right direction.
Last edited by Sparky; Dec 28, 2005 at 01:32 PM.
Yup, couldn't get it to rotate. Trying to trail-brake usually just led to understeer with the RB bar, where I did not have that problem with the stock bar. My slalom and transitional speeds went up some w/ the RB bar over the stock bar. I should mention that I ran on Dunlop SSR's 225 (because they are cheap), not the requisite Kuhmos/Hoosiers. Almost neutral handling came at 44 psi front, 52+ rear!
Originally Posted by tuj
GAH!
-the fact that the guys on the RB bar were 1-2 after day one of Nat'l should say that the RB is not uncompetitive. Is it the best setup? That's still debatable, as we've only run these cars for 1 year of solo2.
-the fact that the guys on the RB bar were 1-2 after day one of Nat'l should say that the RB is not uncompetitive. Is it the best setup? That's still debatable, as we've only run these cars for 1 year of solo2.
However it is hard to argue that when the conditions were warm and dry and the course had a good balance of sweepers and slaloms the RB cars were over a second off the pace, I dont think Eric and Phillip forgot how to drive overnight, just a matter of that big bar killing them in the long turns. While cars with MS, OE and TRX8 swaybars were all within a tenth.
Originally Posted by whiterex
Stock bar is 27mm(I think) and the RB is 32mm.
I figured you could buy the mazdaspeed front sway from the www.mazdamotorsports.com site, but I just looked and didn't see it. Maybe you could send them an e-mail.
Ronnie
Ronnie
Originally Posted by NVMyRX8
Isn't the mazdaspeed bar 27mm , just like stock, but it has thicker walls. Making it just stiff enough for some needs.
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tony_673
Series I Wheels, Tires, Brakes & Suspension
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