Cobb rear swaybar installed.

[Mid_Life_Crisis]

I am able to get a fair amount of oversteer on my stock 08 MS3 without too much over exuberance in tighter turns..not a slow roation but fairly abrupt rear end "let go's". I would be reluctant to stiffen up the rear sway on my car without some major pansuspension modifications. The MS3, to me at least ,seems to handle w/o the noticeable oversteer or "push" that is associated with most FWD's....what some feel is oversteer can be significantly remedied by tire choice. With a set of Kumho V700's, the only end that lets loose for me is the rear (with the DSC off obviously).

Some of my past FWDers have benefited from a stiffer RSB to counteract understeer but I think Mazda has set things up pretty decently straight from the Factory.

While a stiff set-up is needed for the track and fun on the street if road conditions are "track-like", going around a fast street corner with a frost heave or sunken depression can ruin your day in a hurry. A stock suspension set-up is easier to save than a non compliant comp. configuration.

This is why I keep harping on the point that if you keep the factory front bar and put in the Cobb rear bar, go with the milder of the two settings. I agree that the factory did a pretty good job, so you don't want to go overboard with the changes.
With the Cobb bar on the milder setting, when I drive through the twisties, the car tracks flatter during the right to left and left to right transitions. I have no idea what it would do under race conditions, but for just having fun on a winding back road, the changes I'm experiencing make it a blast. I have much more confidence in the car now. On a race track or an autocross course where you are deliberately trying to make the back end come loose in a controlled manner to get around a tight turn faster, I have no idea what effect the bar would have, but I don't do that stuff: I just like to go fast down windy roads, and this bar makes that a lot more fun.

 

[2ManyCars]

This is why I keep harping on the point that if you keep the factory front bar and put in the Cobb rear bar, go with the milder of the two settings. I agree that the factory did a pretty good job, so you don't want to go overboard with the changes.
With the Cobb bar on the milder setting, when I drive through the twisties, the car tracks flatter during the right to left and left to right transitions. I have no idea what it would do under race conditions, but for just having fun on a winding back road, the changes I'm experiencing make it a blast. I have much more confidence in the car now. On a race track or an autocross course where you are deliberately trying to make the back end come loose in a controlled manner to get around a tight turn faster, I have no idea what effect the bar would have, but I don't do that stuff: I just like to go fast down windy roads, and this bar makes that a lot more fun.

Ok so you now have me thinking about doing this again! This is exactly the type of driving I do and what I'm looking for.

 

[Mid_Life_Crisis]

Ok so you now have me thinking about doing this again! This is exactly the type of driving I do and what I'm looking for.

The rear bar is an easy swap that gives a noticeable improvement. Just don't make the mistake of thinking "if a little stiffer is better, then a lot stiffer must be better yet!" If you keep the stock front bar, (swapping it out looks like a nightmare to me) go with the milder of the two settings and have fun.

 

[2ManyCars]

Did the rear swaybar kit from Cobb include the new bushings? It was not clear on the MS site.

 

[redspeed]

The MS3, to me at least ,seems to handle w/o the noticeable oversteer or "push" that is associated with most FWD's.

This is the first time I read about somebody saying that FWD cars are prone to oversteer.

From Wikipedia on FWD-"Predictable handling characteristics: front-wheel drive cars, with a front weight bias, tend to understeer at the limit."

 

[sierra248]

Add to Wiki page "Unless you bolt on a thick rear sway bar"> Lift Throttle oversteer is whats happening to these guys and yes it is oversteer and yes its controllable(Sometimes Scary), but be careful if you beleive above. I owned a Sentra Se-r and if you think our Speed3's are loose FWD cars, go drive an old Se-r (94 mine was), they had crazy understeer and were on 185/60/14's stock dunlops. I miss that car, it was my first new car also, also a C&D 10 bester for like 4 or 5 years.
Tom

 

[redspeed]

Can you explain that again?

 

[sierra248]

Even Stock our cars will do it.

Go around a High Speed On-Ramp (Track be way Safer) and carry allot of speed in, once the suspension is set=

Lifting off the throttle will tighten the line. = OverSteer.

Stepping on the Gas will loosen the line. = UnderSteer.

Its Fun once you master it, you can never turn the wheel, just keep wheel turn same amount thru the entire corner and control where in the lane you are with the Go pedal.

I went looking for a photo from one of the magazine where there is smoke coming off the rear tires going into a corner, Anyone remember which mag that was. It was either at Willow Springs or Laguna Seca. Was one of the big mags also, like car and driver or road and track, Can't find the damn pick though. I also remember seeing a video on you-tube of a member at the track on a track day and he got her very loose. Can't find that either.
Tom

 

[fasteract]

This is the first time I read about somebody saying that FWD cars are prone to oversteer.

From Wikipedia on FWD-"Predictable handling characteristics: front-wheel drive cars, with a front weight bias, tend to understeer at the limit."

I am famous for saying "over" for "under", or vice versa..at least I got the "push" part straight meaning, I meant, understeer. Thanks for the copy correction.

 

[redspeed]

Lifting off the throttle will tighten the line. = OverSteer.

Stepping on the Gas will loosen the line. = UnderSteer.

Ok, I see what you're saying, but that doesn't mean that fwd is prone to oversteer. Yeah, the ms3 and some other fwd cars with good suspension setup can handle and induced into oversteer, but that does not apply to the majority of fwd cars.

 

[sierra248]

"Ok, I see what you're saying, but that doesn't mean that fwd is prone to oversteer"

Not gonna argue that. FWD are definitely more prone to Understeer then Oversteer but you put a big rear bar on a FWD car and it will oversteer ALLOT and its not the controllable type that a RWD car has, it can get hairy fast. The big advantage to FWD is that the best thing to do when sliding a FWD car is to let off or even brake, especially when pushing wide, do that in a RWD car and your spinning. People argue the FWD vs RWD thing with me allot being the owner of mostly FWD cars and I always say."RWD is better for handling, but I can drive right up to the limit(even past it) and if things get hairy, I can let off or brake" try that in a Vette and your spinning. Now if you do get to drive hard often, the trend in RWD, or almost all AWD cars is to make them understeer now also with oversteer being a power induced thing. Drive the new 3 series into a corner hard and it feels very FWD till you get on the gas to induce some oversteer.

Now after saying that, I'm thinking that just the Cobb Rear Sway bar with this car would be a nice upgrade, but I'm not lowering or putting a front bar on either. I'm getting old, like the ride and handling as is, except for the slight delay between when you turn her in and the suspension settles, the rear bar may be enough to stop that, plus I am gonna go a little crazy with sticky Falken RT-615's in 225/45/18 when i wear thru my Stock ones and that should get her to stick more then I ever will need, and still ride well. Wasn't trying to argue with ya at all redspeed, just explaining my little knowledge.
Tom

 

[redspeed]

Ok got ya, good stuff.

 

[happy and angry]

Not gonna argue that. FWD are definitely more prone to Understeer then Oversteer but you put a big rear bar on a FWD car and it will oversteer ALLOT and its not the controllable type that a RWD car has, it can get hairy fast. The big advantage to FWD is that the best thing to do when sliding a FWD car is to let off or even brake, especially when pushing wide, do that in a RWD car and your spinning. People argue the FWD vs RWD thing with me allot being the owner of mostly FWD cars and I always say."RWD is better for handling, but I can drive right up to the limit(even past it) and if things get hairy, I can let off or brake" try that in a Vette and your spinning. Now if you do get to drive hard often, the trend in RWD, or almost all AWD cars is to make them understeer now also with oversteer being a power induced thing. Drive the new 3 series into a corner hard and it feels very FWD till you get on the gas to induce some oversteer.

If you stiffen the rear of the car enough that your car has a tendency to oversteer rather than understeer, hitting the brakes is going to induce a spin just as easily in your FWD car as it is in a RWD vehicle.

Drivetrain dictates what you can do with the throttle, but vehicle dynamics is not dictated solely by drivetrain. An example of what I mean: Say you've thrown that swaybar on, and now your Mazdaspeed3 oversteers in a corner when you come off throttle. Say you try to power through a corner on throttle and you start to understeer. Say you try to correct by hitting the brakes. You come off throttle, front end traction improves with no power to the wheels, and the rear end starts to come around just as you hit the brakes. What's going to happen?

It's not going to be the same sort of uncontrollable spin as a car with a more even weight distribution, or throttle controlled oversteer, or a car with more weight in the back from a diff or an engine (say, in a porsche), but you can still get into an uncontrollable spin, especially when you've changed the natural characteristics of the car from mild understeer to mild oversteer. So in general you're right, but be careful when you start playing with vehicle balance. Even and FWD can spin under braking in a corner.

 

[Mid_Life_Crisis]

The Mazda engineers are not fools. They were creating an affordable sports hatch. They may have erred a little on the conservative (safe) side, but they wouldn't knowingly release a car that was absurdly far off from proper balance. I mean, they have Zoom-Zoom to live up to, right?
All of which just supports that dead horse I keep flogging. Make modest changes at least until you have time to properly test the effects they have. From what I can tell, the suspension "experts" seem to agree that the car needs to be a little stiffer in the back in relation to the front than the stock setup is, but nobody goes crazy with the changes. Cobb's springs go up 15% in the front and 25% in the rear and both are progressive rate springs. A modest stiffness increase all around, with a slight increase in rear as compared to the front. I still maintain that they have adjustability on the rear bar but not on the front so that the rear can be installed by itself and make an appropriate increase in rear stiffness as compared to front or both can be replaced and still keep the proportions correct.

 

[sierra248]

For those of you that did just the rear bar, does it eliminate some of the delay before the suspension sets in a corner? U prob know the feeling im talkin about, the delay between when you turn into the corner and when the suspension really glues down? Feels like just a hair to much body roll before it plants its feet.
Tom

 

[Mid_Life_Crisis]

For those of you that did just the rear bar, does it eliminate some of the delay before the suspension sets in a corner? U prob know the feeling im talkin about, the delay between when you turn into the corner and when the suspension really glues down? Feels like just a hair to much body roll before it plants its feet.
Tom

All I can say is that the car tracks flatter now. I don't get the feeling like the back end is trying to roll more than the front end, like I used to. I don't race the thing, I just drive fast down winding roads, and I am much more confident in the car now. I don't know if that answers your question or not, but it's all I got.

 

[sierra248]

Sounds like what I'm looking for. Good info.

 

[2ManyCars]

Does anyone have the torque numbers for the bolts for the rear sway bar and endlinks?

Thanks

 

[fasteract]

The numbers are the same for both parts...29.8-40.3 ft/lbs with blue Locktite suggested

 

[fasteract]