DomFD3S

This thread is interesting.

Per Racing Beat's website, the front sway bar is solid, while the rear is hollow.
http://www.racingbeat.com/FRmazda3.htm

I'm really annoyed w/ the bar not being tempered.
Despite it being "unnecessary" per the manufacturer's recommendations, this doesn't sit well w/ me for a "sports car".

But I'm going to see what happens w/ this situation. This is definitely a thread I'm keeping an eye on.

Streamline

Could these untempered sway bars be what is causing some FDs to result in a "I installed some springs and my FD is lower/higher on one side" thread?

DaveW

That's BS (Racing Beat's statement).

If it bent, it WAS necessary, no matter what they said!

Dave

gen3rx7

I just spoke w/ RB a few minutes ago & I'm shipping my front bar back to be inspected. I'll check for any bends once it is off the car. I explained to Jim that it was installed correctly and he is cooperating to help diagnose how this could have happened...

dlarson101

Well I just removed my rear sway bar and it is definatlly bent. I matched it up with the stock one and it is bent in two directions, out and up. Both of these bends will cause the car to sag on ths side(left rear).

I took some photos while it was on the car and some side by side with the stock bar.

In the first photo you can see how it forces the mount out and up. If it was centered like the second photo it would not force the LR wheel up and elimiminate sag on this side of the car.

Looks like I will be contacting RB tomorrow as well looking for what, I don't know. If this is how they just are then I will be seeking a refund and going with one of the others mentioned in this thread.

DomFD3S

I've decided to assembly my own Tri-Point style thread. As for the rear sway bar, not sure if I will do the same...but a possibility.

Doc-1

iTrader: (2)

A note here, both of the RB bars I got were/are solid. The Mazdaspeed are both solid as well. I was surprised to see the OEM rear hollow.

It appears to me that Mazda was looking to take for ways to take every ounce of weight possible off the car, to make it hollow. I does save a pound or two.

adam c

iTrader: (2)

A hollow bar will have the same effectiveness controlling sway as a solid bar, and will weigh less.

DaveW

Essentially, you are correct. However, to be completely accurate, a hollow bar of the same OD and geometry will have almost the same effectiveness controlling sway as a solid bar, and will weigh less. The torsional stiffness is proportional to (OD^4 - ID^4).

It will also tend to yield at a slightly lower loading, given the same material and hardness.

This is the nit-picking engineer in me coming out...

Dave

adam c

iTrader: (2)

Typical engineer . Argues with you, and then proves you are only 99% right

DaveW

Yup! I can be a real PITA!

Dave

Doc-1

iTrader: (2)

Dave while true ......the real golden BB is that you can stack one inside of another. What you can do (if very clever) is have an progressive sway bar. Only DoD and formula 1 can afford. The early versions had an issue for breaking...if you can call it that...they exploded.

Doc

DaveW

OK. Explain to me why that would be progressive.

I believe it would still be linear.

If both bars (one inside the other) were twisted the same # of degrees, and both were constant (but different) torsional rates (which they would be), their rates would be additive, and the sum of the two rates would still be constant the same way a single thickness bar would be. That would still be true even if they had different arm lengths and rotated different, but proportional, #'s of degrees.

Dave

adam c

iTrader: (2)

Dave is only 99% right, so I am going to argue with him, to be a PITA.

If Delti Fi * Gamma squared + 1/2 interior radius of softer bar = 3 sigma's then Dave = only 99% right. Please try to prove me wrong ..........

Doc-1

iTrader: (2)

Dave

What was used... different rates as a function of material and diameter. Stops were incorporated to force rate changes as a function of wheel movement. There for the first several inches were relatively soft and the last inch or so was used to absorb the entire weight of the vehicle. This allows wheel movement without transmitting the shock to the vehicle. By using this approach a stabilized system could be incorporated with some effectiveness. However limits of both sides of the system do exist. In other words it is not a 100% solution, but a very good system solution that covers 90% of the envelope. The hollow torsion bars fit one inside of another and give a practical length of the total. The mechanical stops force a change from one rate to another. The system can be preloaded, each torsion tube can be preloaded. Each wheel can be tuned. The tubes can be made of carbon fiber or any number of metal alloys.

Hope this helps
Doc

DaveW

OK. Progressive engagement => progressive rate. That makes sense. I posed the question because your original discussion didn't say that. Thanks.

Dave

DaveW

Dave

Fritz Flynn

iTrader: (263)

This thread is disturbing

DamonB

Easily accomplished with the linkage to a t-bar type bar if someone chooses to get creative.

GoodfellaFD3S

iTrader: (213)

Yes it it. I'm glad I still have my stock swaybars on the car.

Doc-1

iTrader: (2)

Dave
Sorry, it was me that did not provide enough information for my statement.

DaveW

No apology necessary. Thanks for explaning what you meant! I just like to understand stuff.

Dave

gen3rx7

Sent my front bar Fed-Ex today to R/B, hoping for a resolution soon!

Track event at Thunderhill next month I need to get it back on the car...

R. Gambino

Gen3 I sure hope you securely boxed up that bar. Evidently thier UPS delivery man is rather "hard" on his packages, as evidenced by RB statement that the possible reason for the returned bent swaybar might have been caused by UPS.
AMAZING

Doc-1

iTrader: (2)

Yep I was told that I did not ship the Racing Beat sway bar right. That UPS had "damaged it" go figure. Now if I set it by US Mail they have a right to bitch.