Has anyone experimented with a Big Bar Soft Spring setup before? It seems like this might be a good thing for our cars over a conventional setup. Any opinions?

 

are you looking for a nascar setup?

 

No just noticed a lot of stuff people where saying about their setups and just wondering if a setup like that might actually work on our car. Just thinking out side of the box but I should have known I'd get no actually input from anyone just stupid comments from people.

 

have you researched where bbss setups are useful?

I asked you that questions because the setup is for round track racing.

 

Why does it seem like it would be a good thing for our cars over a conventional setup? It seems to me that the conventional setups work pretty damn good so I am curious as to how you came to the conclusion that a BBSS setup would be beneficial at all.

 

Everyone has had an issue with the rear spring if the drop is to low. From my understanding of bbss is by using softer front springs and bigger sway it puts more grip to the outside rear so you can run a stiffer rear or keep the rear sway on it. So you can keep the back lower with out bottoming it out. I'm new to the bbss setup so from my understanding of it it seems beneficial to a common problem we have.

 

Who is everyone? I am not aware of any problem with the rear springs. There can be a problem if you drop the car too low or are using crappy shocks/spring setups but that is only the fault of the person lowering the car too low. And a stiffer rear bar will not help with bottoming out due to being too low.

 

bbss setups are used to soften the front springs and increase the stiffness of the rear outside for cars that are constantly turning left (nascar). I would not recommend this kind of setup for a car built to be agile through turns.



but you maybe one of those guys just trying to get as low as possible for some sort of fad reason.

 

There are aftermarket setups that use stiffer bars in relation to springs, but not to the extent of a BBSS nascar setup. Compare the Racing Beat bar/spring setup compared to Mazdaspeed bar/spring setup. Racing Beat went with a large bar with only a 30% spring stiffness increase. Mazdaspeed increased the spring stiffness more (80% increase front, 69% increase rear) compared to the anti sway bars.

If you have any of the "large" adjustable bars (Whiteline, Agency Power, Progress Tech, Tanabe), you are probably running a form of a BBSS setup (assuming you aren't running 7k springs.

It doesn't seem like you fully understand why you are asking this question to begin with. Care to elaborate why you think a BBSS system is "better", or what do you want your end goal to be?

 

9krpm- I said in the first sentence you quoted the problem is from dropping it to low. Anything more then a half inch of drop in the rear can cause problems. I know we can't run a true bbss setup but it is possible to use the idea of it. I never said it would be better just that it might benefit us if it's looked into. I've noticed people are running larger sways upfront and getting less under steer. Why? From my knowledge a stiffer front creates more under steer. Just a lot of stuff on this forum that people are doing that is similar to the idea of a bbss setup. A more planted outside rear Tire would make for great exit speeds cause you can get on it that much sooner. I never said it as better or the best for our car. I don't know enough about it to make those claims. It just seems like he goal of a bbss setup would be great for autox if adapted right.

 

Small Bars / stiff springs, or big bars / soft springs - MX-5 Miata Forum
Here is a link to a miata forum that is where my thought is.

 

What people are making these claims? If these people are making these claims, then they don't understand suspension systems and tuning....

 

[quote=JCrane82;4328769]
They assume they know everything about cars. They should be the one who engineered the car at the first place.

 

[quote=JCrane82;4328769][quote=xbartosx;4328570] I've noticed people are running larger sways upfront and getting less under steer. There are multiple threads on the topic. You guys are making the claims since almost everyone is running a front sway and no rear sway. I'm not sure where the thread is but it explains to another member that most people are adding a front sway and removing the rear to correct his under steer problem.

 

Took a quick read of that thread. Although some of the information is accurate, it doesn't seem like anyone there fully understands this either. Everyone is speculating and not understanding the full system.

Anti-sway bars are "band-aids", in a sense, because they add roll stiffness without adding jounce stiffness. If we all didn't care about ride comfort (only cared about performance) we would not need anti-sway bars.

 

I would love to see these multiple threads, because I guarantee someone is not removing the rear bar and getting more oversteer. Someone may think that is what they are doing......but they are wrong. There is a lot of incorrect information on the internet.....learn to syphon out the BS.

 

Also if adding a front sway to decrease under steer isn't true then a bbss setup wouldn't work at all. So people do understand suspension and tuning even if you don't understand it. Now if all your going to do is attack things I'm say then stop posting.

 

I am not trying to attack you, but you stated something that doesn't make any sense in the field of suspension systems. Just because I disagree with you, how is that attacking? Other people will have different views as you, and if you can accept those views you will learn about how these systems really work.

A BBSS system isn't about adding a front sway bar to decrease understeer, so I am not sure where that claim came from.

Since it seems you are looking for a spoon fed answer, here it is:

When talking about understeer/oversteer, it means the cars tendency to push (understeer) or rotate (oversteer). The equation that determines a cars understeer/oversteer tendency is the ratio of front roll stiffness to rear roll stiffness. As said before, many things can change the roll stiffness of a car (i.e. tires, alignments {both toe and camber}, anti-sway bars, spring stiffness, etc.).

The idea of a BBSS is to make a good handling car (high roll stiffness) without making it beat you up on the street (soft spring stiffness). There are many downsides to a BBSS system. One being that anti-sway bars do not affect brake dive and acceleration squat. The only race cars that I know of that utilize a BBSS system is for circle track, and usually that system works because they need a compliant spring over dirt. I am not aware of any road racing cars that run large a BBSS system.

Remember......that doesn't mean that there aren't race cars with big front sway bars......it just means that in relation to the spring stiffness, that big front bar isn't stiff. You have to look at it as a system.

 

^good info. its important to understand that you must look at it as a full setup. I like the way you laid that out Jcrane.

 

You've got it backwards, adding a bigger front bar doesn't help understeer problems it makes it worse...

Adding a stiffer/bigger front sway bar INCREASES understeer.
Adding a stiffer/bigger rear sway bar increases oversteer.
Adding a softer/smaller front sway bar DECREASES understeer.
Adding a softer/smaller rear sway bar decreases oversteer.

 

Yes you are all correct if I was talking about a conventional setup. You are all assuming that traction is maxed out on both ends. Just cause a car has suspension does not mean that it has it traction maximized for that vehicle it's only maximized for that setup. You are looking at the car as a whole saying that it has 100% traction for that car which can be true even when each individual tire does not have maximum traction. You talk about understanding everything and only looking at it one way when I'm looking at something out of the normal. So I'm willing to look at something new rather then something you are all doing. Bbss vs conventional setups are most common in circle tracks as of recent but have been debated on for a long time in all racing styles. A basic car setup has to have moving parts by increasing suspension stiffness you increase body twist and by decreasing suspension stiffness you decrease body twist. Since our cars are so rigid normally it only makes sense to use it. My original question was has anyone looked into it for the rx8 not questioning my knowledge of suspension and how it works. Clearly by all of your answers none have you have looked into it on a car that loves suspension travel and was built from the factory with a relatively soft suspension. I'm not stating I'm right or wrong there is no way to be right or wrong when it comes to this topic. I'm just looking at things from a different light. Yes a stiffer spring will increase traction on a glass surface but to stiff on an uneven surface will decrease overal traction. Since most of the roads in pa and most parking lots are craters of death it only makes since to build a suspension that can handle the extremely uneven surfaces.

 

In a bbss setup the idea is to put as much weight on the outside wheel so by increasing the sway bar and decreasing the spring stiffness you can in fact decrease under steer. Suspensions are not as cut and dry as you stated. Your assuming it's on a conventional setup and that Im using the sway bars to fine tune the suspension.