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Discussion Starter #1
In addition to my AW11, I also have a Miata, and in reading through a thread there recently, seen here, they discuss sway bars. From what I gather, they basically claim that sway bars, ultimately, cause the car to lose grip, and, overall, cause the car to handle with less speed, and less cornering potential. They make you "feel" like your car is going faster because you corner flatter, but with the way they force pressure to the outside of the tires, they ultimately make your car handle worse.

I have a nice set of adjustable sway bars ready to go on my AW11, and this goes against everything I've ever heard, but I was curious what everyone's reaction here would be.
 

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funny, a friend of mine who autocrosses and is divisionally ranked campaigns a Miata R and has a McLarge-sized NASCAR-style front swaybar to augment the R's handling.
 

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Also, If you have stock suspension or not. After driving around without one for almost a month, I can tell you it makes you faster. After cornering hard on the exits i would slide. Not anymore with the bar. They make a difference for the better. Too much roll puts a lot of stress on the tires. Im guessing why I was sliding was because the roll was putting to much force on the sidewalls and they would flex.

Having a stiff chassis and a soft suspension wont yield good results with a sway bar. You have to have both to match.
 

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If adding larger swaybars causes handling to be worse then why would ALL classes of racing like World Champion Series add bigger swaybars?

Swaybars per say do not cause the car to handle worse, it's adding swaybars that are not tuned to the rest of the suspension. I could take the swaybar off my Nissan Frontier (which makes the H&T bar look like a toothpick) and put it on my MR2 but because it is bigger doesn't necessarily mean it will make the car handle better.
I have the Suspension Techniques sway bar kit, front and rear. This kit was designed for the MR2. If I put a swaybar kit from a Camaro on my MR2, guess what? It will probably make the handling worse.

It's all about tuning the suspension with components that complement each other. Swaybars are just a small part of the equation.
 

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Body roll slows you down. Period. You do have to be aware of understeer/oversteer and tune/fit the bars for optimal handling. Claiming sway bars "ultimately make the car lose grip" means to me that the car in question is expirencing understeer and the driver has not set their suspension up correctly... Either the bar(s) are not properly sized/adjusted or that the car needs better tires. Not to mention camber adjustment, ride heights, etc. Sway bars are only one piece of the entire suspension system.
 

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I have read enough books to convince myself that what the Miata folks are saying is actually true, but there is a huge caveat that must be included. "In ideal conditions."

Unfortunately for us, the Miata with its carefully designed double wishbone suspension comes a lot closer to ideal conditions than the AW-11 and its struts. They (Miata) may gain enough camber as the body rolls so that it (roll) doesn't really hurt them, we (AW-11) definitely do not.

Clear as mud huh.
 

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Discussion Starter #7
Well, it has me worried in another way. I am putting ST sway bars on my AW11, but while I HAD planned on going with stock springs, Tokico adj. shocks, and ST sway bars--the thinking being that it ALMOST handles good enough for me now, the ST sways and adj. shocks cleaning it all up enough for me for now, and sometime down the line maybe going full coilovers. Now I'm thinking springs might've been a good idea, regardless of how they change the roll center, etc.
 

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What Kirk Said:

It's gotta be a PACKAGE.

This from GRM.

Quote:
I'm not talking about street cars here; I'm talking about a very stiffly sprung race car.
With the nearly infinite selection of spring rates, and the ease of swapping them (I've got them down to under an hour now), do we really need anti-sway bars? Why not balance the car with springs only and drop the sway bars altogether? Also, the anti- sway bars are not light, and ditching them will save weight.
I admit the ability to fine tune with an adjustable sway bar is nice. After they are "tuned in" to the liking of the driver, however he/she often will not adjust them again. In this case, why not just get the spring rates "tuned" without anti- sway bars? Please school me.

Walter McKinney


That is a good question, as we have seen a few fast production-based race cars run sans bars, but that seems to be a rarity. Looking for a little more in - depth information, we posed your question to Jay Morris, owner of Ground Control Suspension Systems.

"Well, M. Schumacher has sway bars, so I have decided to approach this from the 'why' pointof of view as well as the 'why not' point of view.
"Almost every form of road racing, and now even autocross require some form of tire management. Modern tires are now soft enough that even the club racer can lose grip toward the end of a sprint race if the tires are worked too hard.
"Here is the key:
"The heat of the tire is directly related to the force put on it by th weight of the car via the springs. Tires like to be pushed just the right amount to get maximum grip and traction.
"By the time you stiffen the springs so much that body roll (even on an F1 Car) is minimized enough so that all four wheels are somewhat happy with their geometry, you will have such stiff springs that you will overheat the tires. Anti-roll bars are a method of stiffening the car, puhing on the tires just enough in the turns, but not too much on straights or bumps.
"So we've discussed the 'why' and the 'why not'; let's discuss the 'what if'.
"What if the car had no anti-roll bars along with springs that kept body roll to an arbitrary 3 degree roll? Race tires would get too hot, street tires would be pushed so hard they slide, and grip would probably be very poor because of reduced compliance over small bumps.
"What if the car had no anti-roll bars along with springs that kept body roll to the same 3 degrees? The car would dive so much under braking, and would also have a tendency to lift one (or more) wheels in turns because anti-roll bar leans on the outside tire as well as pulling up on the inside tires.

"What if the car had springs that were just stiff enough to keep the tires from overheating in the event-whether it be a 1-minute autocross, a 45 minute SCCA national or a 10-lap stint ona four-stop strategy- and anti roll bars that were tuned to roll to 3 degrees? I believe this owuld be the compromise that would be fastest around the course.
"And regarding the weight of the bar itself, most cars can save weight by optimizing pickup points and using hollow tubing.
 

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The car manufacturer Morgan doesn't like using roll bars in any race cars and the head of the company stated that a properly designed race car suspension wouldn't need roll bars. They are used to tune imperfections in the suspension.
 

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Discussion Starter #10
Red 20V said:
The car manufacturer Morgan doesn't like using roll bars in any race cars and the head of the company stated that a properly designed race car suspension wouldn't need roll bars. They are used to tune imperfections in the suspension.
I have read the same thing. Obviously street cars rarely enjoy perfectly tuned suspensions.
 

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Far more variables go into it then you could possibly imagine. The variable of tire data alone is insane. In theory though, yes, bars limit ultimate grip.

But every disconnect your bar and try to drive through a slalom without one? Very interesting things happen...

It's a pretty common trick for autox'ers to disconnect a bar. More common amongst the FWD crowd (read Honda), they like to pull the front bar and only run a fat rear. Makes the car rotate nicely. It also makes them wallow through a slalom pretty bad.

Setup the car how you feel comfortable driving it. Personally, I do prefer a lightly 'barred' car with heavy spring rates. But that's how I drive a car and that's how I like it. Now, there's always the difference between the tale of the stop watch and the tale of the wet seat as well. What may be comfortable may not be fastest, and what may be fastest may not be comfortable.
 

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little tidbit of info:

I'm not running a swaybar up front right now in my AW11. Yes, you saw that right. Makes it rotate, brake, and turn in nicely on snow, ice, and rallyX. I put those rubber doughnuts that eliminate a coil in your coil-sprung suspension to compensate for the lost roll stiffness up front.

I have stock springs at the moment BTW.

That said, a lot depends on the conditions as well. Would I dare disconnecting the front bar on pavement Autox? No matter how bad the rain, no matter how tight the course, I probably won't. It just gives the vaguest of feelings on higher speeds. I'll stick with the huge spring stiffness difference between front and rear, and put a bar up front that's larger than the rear.
 

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Fred Puhn says that sway bars are good :) (in a much more complex way that I cant even fully understand)

;)

Suspension works together to perform properly.. that includes sway bars which are an important aspect just for a car to be roadworthy, that's why even non performance vehicles are often equipped with large sway bars
 

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It's got so much info it's unbelievable
 

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As I've said in every discussion of this type: Bars are good, but should be the LAST piece of the puzzle - after struts, springs, tires, and alignment. Get the base down, and tune out the little bit left with good adjustable bars.

Street cars have bigger bars, because 95% of the street car buyers out there would not put up with spring and strut combinations that optimize handling. Bars are a band-aid to cover up a "compliant" suspension.

I run an adjustable 11mm rear bar (1mm larger than the stock '85 bar), and I assure you, a one-notch adjustment will alter the handling noticeably at the limit.
 

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ITA-MR2 said:
As I've said in every discussion of this type: Bars are good, but should be the LAST piece of the puzzle - after struts, springs, tires, and alignment. Get the base down, and tune out the little bit left with good adjustable bars.
Absolutely.

From the GRM quote, stiff springs overheat tires? In corners, a car of X weight that rolls 3 degrees will put Y force on the tires. How it got to 3 degrees doesn't matter. So this "tire overheating" must happen on the straights? I'm really lost here and don't see how that makes sense.

That Miata thread is kinda silly because, like someone mentioned, they're talking in the context of cars that can run ideal spring rates, which are going to be higher than any plug and play spring set for an MR2, and probably any streetable spring set on a miata. Unless you're running springs at or above the rates Norm is running (i.e. full race setup), a sway bar will help. On my MK2, I'd imagine I'd have to run front spring rates in the neighborhood of 600# or more to be able to do away with my front sway bar. Who wants to drive those springs on the street?

Sway bars are the best thing that ever happened to street cars.
 

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I'm running 350 / 450. Some of the tracks we run are not the smoothest thing in the world, and anything more results in loss of contact. On a couple of tracks we could probably get by with somewhere in the neighborhood of 550 / 700, but I'm not into changing the springs for every track. Additonally, anything harder would compromise wet traction - and we already go full soft on the bars and nearly full soft on the struts for those.
 

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Agree w/ Norm. I run 3000 and 275 on the street w/ a stock front and '85 rear bar on my car. It's a nice setup for the street that autox's nicely and is competent on the track. I run pretty soft in back, but it worked out well because I made a good amount of power for a while and it put it down nicely. The '85 bar was just enough to stiffen up the roll though and make up for the soft spring rate. Personally, yes I'd go a smidge higher if I was to do it again, but for now it's liveable.
 
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