JeffWels

I disagree, this would be true if both the front and the rear bars were the same thickness but they aren't. and yes it does stiffen the chassis. If you put coilovers on the car and understeer severely, then you haven't set them up properly. You need to align and corner weight the car. Then there will be no need for a rear sway bar to correct a problem that won't be there . I personally will only replace both bars at the same time.

JeffWels

Thats exactly my point... if your coilovers aren't set up properly then you will cure one problem by making another. It will just be a dommino effect until you get the initial upgrade right (the coilovers)

hotrod2448

you should look at it like this your springs control weight transfer to the front or rear wheels, your sway bars control weight transfer laterally.You could use stiffer rear springs to accomplish more oversteer but that also effects weight transfer when braking or accelerating which you may or may not want depending on your driving style. Whereas sway bars only affect the cars handling when there is lateral weight transfer.(turning) It all depends on when you want the car to free up, entering or exiting a turn, or in the center of the turn. I do agree you should optimize your alignment first.

JeffWels

All I'm saying is you shouldn't try to cure a coilover problem with a sway bar.

2fast2Furious

I say throw more money at it and make it worse? I sure wish people would spend more money on how to drive then going with a coilover setup and bars all over the place. I bet NONE of these coilover kits pull a higher G then stock, UNLESS you have someone set it up that knows what the hell they are doing. And from reading the posts people don't even know WHY they are installing a coil over kit, Maybe because it looks cool and people like riding on bump stops?

JeffWels

you install springs if you want to ride on bump stops. and like you said setting up the coilovers is 95% of the fight. With coilovers setup properly you will never hit the bump stops. maybe you meant the bumpier ride. the whole point of coilovers is to have a better handling car, which means hopefully never hitting the bump stops.

03EVO8

I didn't know we were talking coil overs. In stock form a good way to balance the car is an alignment with more neg camber in the front and a slightly stiffer rear sway. I haven't driven the car with coil overs yet. Stiffer springs would also reduce body roll a bit and may effect the balance. But then again a anti sway bar is $200 and coil overs abroach $2000. For that kind of coin, I would get second set of rims and some race rubber which would make my track time much much lower than coil overs.

In this month's SCC Dave Coleman has a short article on handling. When it comes to balance he says:
"More oversteer comes from putting more laod on the rear tires, and that comes form a stiffer rear anti-roll bar, stiffer rear springs, or stiffer rear shocks. .... A change in anti-roll bar diameter will make the most dramatic change in hadling balance. Changing spring rates is probably second. Changing the lever arm on a anti-roll bar is third and turning the knob on adjustable shocks is a distant forth. He also says the rubber is by far the # 1 factor for handling. (Back to the buying race rubber before coil overs statement)
Ross Bently in the book "Speed Secrets Professional Race Driving Techniques" also like starting with the anti roll bars for suspension tuning. He says it is the quickest and most effective way to change the balance of the car (read balance as under/over steer).

03EVO8

Please explain to me physically how a sway bar increases chassis stiffness.
And i have already quoted 2 sources that say sway bars are the first thing you use to tune over/understeer.

MYEVOVIII

iTrader: (35)

Another post turned argument.

MGMaronich

fastmarsh

The sway bars are the first item that you should start with after you have the alignment done. The alignment should include the camber and toe adjustments. I won't post my setting because I have a different driving styles than most people.

I have 8000 miles in 3 months on the car, have adjusted the alignment 4 times to get it where I want.

You also need to understand your driving style to whether you are "Overdriving" and making the car push because of style, not mechanics.

I haven't invested in any sway bars yet, as I have tuned out some of the understeer. You also need to drive the car and set it up similar to a front wheel drive. Left Foot braking can also take away alot of the push. This is a technique that is easy to learn.

Good Luck and have fun with the car.

JeffWels

No argument here, and that is a useless post.


03EVO8 I totally agree that in stock form all the car needs is an allignment. I also totally agree that the single most important thing to a track car is wheels and rubber.

All I am saying is he threw on coilovers... now he has a problem with the coilovers. There are so many factors that could be a part of his problem we really can't even make a guess without driving the car. Yes a rear sway bar will fix his problem but in turn may over compensate and create another problem. It also may not... I am speaking from exp. on the FD rx7's, I have never replaced my sway bars on my evo

Also as hotrod stated the sway bars are for the weight transfer of the car. trying to correct this with springs really isn't a good idea.

Since he already has coilovers I say he needs to corner weight and get the thing aligned. I almost gaurantee it will solve his problem.

hotrod2448

I agree if you have coilovers the first thing you need to do is get your car on a set of scales and check your corner weights. It would also be good to put some weight(close to your weight) where you would be sitting in the car so you know what you have when your in the car. Keep in mind if you change your ride heights you need to re-scale your car. Changes in camber also affect your corner weights to some extent.

hotrod2448

Also depending on how bad the bump steer of this car is changes in ride heght will affect your toe and we all know your toe settings make a big difference in the way the car feels.

03EVO8

Yep, no arguement here, (I did use the wrong smilie icon by mistake!).
Seems like everyone is in agreement now. I was also a little confused thinking that Jeffwels was the one that put on the coil overs and was recommending it as a first step.