Has anyone run this in BS Solo? It's listed as 30.4mm but no wall thickness is given. Curious how it compares to RB and Mazdaspeed bars. Looks like it might fit in the middle somewhere.

 

Tanabe is a 30.4mm bar with a 5mm thick wall.
Racing Beat is 32mm with a 4.76mm wall.
For some reason I think the Tanabe was a tiny bit stiffer but I am sure they are close. Either way both are way stiffer than MS.

The MS is 27.2mm with 4mm wall vs OE 27mm with 3.4mm wall.

Not sure on the wall thickness, but this one looks interesting:
http://www.vividracing.com/catalog/p...ducts_id/13158

 

Thanks,

I saw that one as well. Looks like an adjustable RB bar. Unless it's thinner it won't get into the range we need. The matching rear bar is a 19mm which is the same as the RB bar as well. Don't understand how a 32mm bar works with the stock bushings?

 

Come on dude its easy.... When half the stuff you sell is bling it only matters how it looks on the car not how it fits. Getting 32mm bushings would be easy, RB has them.

 

Lol.

 

I am sure they are right and it will fit the stock bushings. A 300lb man can also drive a Miata. Somethings just don't fit right. Not sure why they would sell a trick adjustable bar and not toss in a $15.00 set of poly bushings that are the right size.

 

The RB comes with everything you need.

 

I have that bar, but it hasn't been installed yet. I'm waiting for spring. I got the poly bushings from Summit. They are the greaseable type.

 

Neglecting material differences the different size would put the Tanabe bar at 191% of stock. I wish there was something in the 150-170% range.

 

there is and I'm working on it, just so you know my original supplier didn't deliver despite taking $everal grand of my money and now a lawsuit is looming

I'm talking to another supplier about getting them built, if for no other reason than try to salvage some of my loss

 

I ran the Tanabe front in BS (ever so briefly). I think the RB is steel where the Tanabe is Chromoly. IMHO the Tanabe is a bit stiffer and lighter. For the money, go with the Tanabe.

 

ran the calc's, IMO it's too stiff for just a front bar only in B Stock

 

Teamrx8, what is the calc to figure out which is the best front bar. Share a little knowledge so that we noobs don't have to ask the questions.

 

but that would be a trade secret...

 

we'll I guess I'll be on a drilled MS bar this spring.

 

This will let you calculate stiffness:
http://www.tech-session.com/kb/index...v2&id=105&c=52

For hollow bars, you can calculate the stiffness of the outer diameter of the bar and subtract the the stiffness of the inner diamater (the hollow space) to get a final result. ID = OD - 2 * wall thickness.

I was curious how to compare bars, so I dug up this info from an old thread yesterday. I also was bored at work and made an excel spreadsheet that will let you type in the dimensions and spit out the stiffness.

 

wouldn't the "best" bar, be a matter of opinion. What is best all depends on the driver, and how they drive the car. So with that in mind, what will the stiffness of a particular sway bar tell you, more push, less lean, less push, a little more lean.

 

For your enjoyment...

To find out how much you need to drill on the stock/MS bar to increase stiffness,
use the following formula:


A - Length of end perpendicular to B (torque arm - inches)
B - Length of center section (inches)
C - Length of end (inches)
D - Diameter bar (inches)

 

Right. The fomula is just a tool to give you the relative stiffness between bars. It takes real world testing to determine what kind of stiffness would be best for you.

 

IMHO, aggressive driving style will not be well-served with a stiffer bar. The slow-down caused by terminal push in sweepers effectively negates the time gained in transitions. If you have great speed control in slow corners by minding your entry speed, it is not necessary an Achilles' Heel. Afterall, RX-8 is all about smoothness not hack-saw driving out on the course.

 

There are limits to everything. You haven't experienced understeer until you drive the RB bar with Koni's. The problem isn't turn entry, it's that you can't apply gas until after the apex or you'll push wide. The car just wants to go strait when on the gas. No amount of steering input stops it. About 1/2" of rear toe out will correct it, but then you can't drive you're car on the street with DSC enabled, else it will engage on every corner bringing you to a stop. Try it sometime.

 

I think the opposite is true.

There are other setup changes that can be made to make the car push less in sweepers. Though I honestly don't think we saw any decrease in steady-state grip when we put the TeamRX8 bar on the front. We made some "minor" rear toe changes for the last event of '05 that IMO made the car much more fun and faster coming out of slow corners.

 

we're trying to locate the material now, I want to use a special wall thickness to refine the stiffness range and it's not a very popular size

hope to have some answers soon, I know you've all been waiting a long time

that formula above is not what you need to calculate the difference in the hole position, instead just use (original arm length/new arm length) x (previous change from OE). The original RX-8 arm length is 7.375", so all you need to know is how much you changed it with the new hole position, assuming you shortened the MS bar mounting point by 5/8"

(7.375/6.875) x 12.7% = 13.6% which is still next to nothing because the MS bar is just not stiff enough for a front bar only application

the calculations posted in the earlier thread also assumed all the bars had the same OE arm length, that's not always the case

 

More like (7.375/6.875)*112.7=120.9%. Better than nothing.

 

I emailed them about the wall thickness. They say it's 3mm. Using my ghetto spreadsheet that gives about a 64% increase in stiffness over stock, assuming stock arm length. With 3-way adjustability, seems like it's in the range you're looking for Sparky.