I'd like to know the effective spring rate of the various rear sway bars, including S4 base stock. I'm considering running witout the rear sway bar, which obviously means going to stiffer springs in back to compensate. Purpose: Make the rear suspension more independent, allowing me to put more power to the rear wheels sooner as I exit the corner.

 

i dont think that is a good idea, i was told that running with a swaybar up front and non outback causes the car to twist during a corner and makes the car push, so to get though the corner your going to have to enter it slower

 

stiffer springs themselves make putting power to the ground harder though...

 

Taking off the sway bars isnt a good idea get some bigger sway bars if anything I have ST sway bars on my TII and they are working great for me

 

are you talking about the Suspension Technique sway bar if how muh did you pay and from where?

 

F1's run a front sway bar and no rear sway bar for the exact reason I am looking at it. Cars run lose without a rear sway bar when the builder fails to compensate with increased rear spring-rate. I understand it is an odd set up. I'm just looking for numbers so I can make my own decisions on how to make my car do what I want.

 

hmm, in that case i have no idea, i didnt know f1 cars had no rear anti-sway bar, got any links for more info on this?

 

Dude, you are a f'n idiot. You are overthinking this whole situation. You do not have an F1 car so don't try to mimic one. With that logic - the Space Shuttle is pretty quick, so why don't you line the underside of you car with Space Age ceramic tiles? Don't try to mimic what F1 cars do and how they are designed. That's just not the way to do it.

What's wrong with the kouki T2 bars I gave you, anyway? Put them on with a set of fresh poly bushings and endlinks from Mazdatrix to see how nice life is with stiffer swaybars. One of the Slush Series is usually held in Everett. Get you car ready and let's see you there. Also, for the love of that imaginary being, get some good tires on that beast.

If you do feel that you are smarter than just about anybody else, go ahead and take the bar off the back. Just don't drive it like that except at autoX. You'll see, brainiac.

BlackRx7: I paid $235 for my ST bars through Summit.

 

Bigger is not always better!

I run no sway bar in the rear of my race car. It helped remove some of the oversteer my car had on corner exit and did not effect the car good or bad at any other point during a turn.

I would be willing to bet that 90% of all FC's built for ITS Club Racing run with no sway bar or a very small one.

Just because some company builds something and calls it a performance part does not mean it will improve anything. A perfect example of companies selling "performance" products that reduce performance is this. Most of the late 80's early 90's Volkswages in stock form with good tires can pull the inside rear wheel off the ground on an auto-x course. Having all 4 tires on the ground will ALWAYS grip better than only having 3 (even for just a second at a time). Yet there are plenty of companies out there that sell larger rear sway bars that just cause the rear inside wheel to lift even more.

 

First, my ITS car doesn't have a rear bar. Loose enough as it is.

Second, even with your rear bar you are NOT lifting the inside rear. So if you're loosing traction on the inside rear your diff isn't biasing enough torque. Removing the rear bar won't help you there. If you're loosing traction on both rear tires in a straight line removing the rear bar won't help you there either. Bars have no effect on non lateral loads.

And finally what tires are you running? Get better ones.

Chris

 

Jerk,
I've got the front on with the stock bushings, and love the difference. I had the rear on for a week, and decided it had to come back off. So, right now I'm running your TII front sway bar and my N/A rear and things are better. The great thing about taking parts off is that you can always put them back on (assuming you keep them). Also, according to psychological testing, I am smarter than 98.8% of earths population, so I'll trust my ability to use available information to design a system that performs to my needs. As soon as my car begins traveling at severalthousand miles per hour, I'll be going for ceramic tiles in place of paint I think a silcon compound would also be neccessary for my tires at those speeds.

So, C. Ludwig and ThePartsTrader, any info on torsional stiffness of rear sway bars.

 

No rear sway here either...

 

So, how much stiffer are your running your rear springs?

 

Ok. In front I have 400lb/in Eibachs on Tokicos Illumina with a ST bar set on the soft setting. In back I have 250lb/in Eibachs on Koni yellows and no bar. Ride height is 6" at the rocker panel +/- an inch due to variance for corner weighting. Car is free in and sometimes tight off. I played with some weight jacking this summer to get it to come off certain corners better. For example at Mid-Ohio the two most important corners on the track are right handers. After our first weekend there and being tight off both corners we jacked weight around to make the car go right and it worked very well.

Now that's balance. As far as a traction issue I really don't think removing the bar is going to help you hook up any better. Again, what tires are you using? From your profile I gather that you're running an NA? With any near stock NA (ie: IT prep or no big porting) and DOT-race tire you should not have traction problems coming off a corner. My car will spin the inside rear off tight corners on ocassion but that is due to a worn out diff and not poor suspension setup or an over abundance of power.

And regardless of what you scored on you ACT I'd like to recommend Carrol Smith's series of books.

Chris

 

His, and other, books are why I'm looking at this set-up. Intelligence does not give me a license to go about experimentation hap hazard. It merely gives me an edge in assimilating and using information and more importantly, concepts. Thanks for the info.

 

ThePartsTrader

Front drive cars can lift the rear inside tire because the outside tire has enough grip to carry the load of the rear end of the car. So 4 wheels are not needed while cornering, and no perforance is lost. There is a similar situation with 911's. They start to lift the front inside tire ooff the ground when they accelerate out of corners.

So 3 wheels are just as good as 4 in certain situations.

 

I was just using the VW sway bar as an example of manufacturers selling "performance" items that actually reduce performance. I was not comparing any part of the workings of its suspension to that of an FC. (Bad example I guess).

{this rant only applies VW Sciroccos (and simular VWs in general}
I disagree with you on your theory of "4 wheels are not needed while cornering" when it applies to the VW (I cannot speak for the Porsche as I have not driven the car you referred to).

Having campaigned a modified '87 VW Scirocco 16v for about 3 years in various SP categories of Solo II I know first hand that having the inside rear wheel on the ground can make the car faster. Your theory applies any time the front end is pushing, if it is already sliding I agree a bit more grip in the rear will not make a significant difference. But my VW did not push all the time. On sweeping turns or decreasing radius turns the inside rear wheel would lift while the front had plenty of traction causing oversteer. Changing the suspension setup to cut down on the amount of lift also cut down on the amount of oversteer on sweeping turns.

Take your pick.. larger sway bar that slows down the car in some instances. OR small/NO sway bar that helps in some instances. I would error on the side of helping.
{/ end rant}



I have not decided if I agree or disagree on this but the following is a general theory about sway bars I have heard a few times the years.

A sway bar is essentially a spring that works only part of the time. How do you properly valve shocks to handle a spring rate of (example numbers) 400lbs when both wheels hit a bump AND also handle a spring rate of 450+lbs when only one wheel hits a bump?

BTW: the first person to ask me the previous question is a 2x DSP Solo II National Champ that runs NO front or rear sway bars on his car.

 

Three wheels can only be better than four when you lack the power to exceed the road handling limits of the three wheels.

I'm looking for better suspension not because I have lots of horse-power now, but because my suspension is shot and I'm not a fan of spending money twice. Since I need to replace stuff now, I'd like to be ready for the hp my future mods will yield. The way I look at it, you can never have too much (balanced) grip.

 

Hey, I still have the stock shocks and springs off of my car. Do you want them to experiment with? Same deal as my old sway bars. By the way, they are not shot.

Please, get some good tires.

 

If you've read the Smith books you'll know he's not a big fan of doing what you want to do. He's a proponent of soft springs, big bars. I know, I know, F1 runs stupid stiff springs. Forget it, different ball game.

Get some good tires. Talk to your nearest Hoosier or Goodyear (race tire) dealer about some used tires. Alot of the fast guys will discard them after a couple sessions. Hoosiers don't last very long but tires with some heat cycles left in them can be had on the cheap.

If your suspension is shot you're not going to optimize anything you put on the car and you'll never get consistent performance. My advice is to forget the springs and replace the bushings and do the toe eliminators. You're one of the first people I've heard admit that our 15 year old cars might have a worn out suspension (ie: "do my adjustable shocks still work?). It's very possible with worn out bushings that the whole deal is putting itself in a bind and it's most certainly not maintaining a proper alignment for you.

Bottom line is that with an NA you should not be spinning coming off a corner on a road course. AutoX maybe. To illustrate my point realize that in most cases when my ITS car goes big time loose mid corner the best way to recover it is to stand on the gas! The car doesn't make enough torque to spin the tires but by putting the hammer down the added weight transfer to the rear helps settle the car. Good tires will help put the power down and pick up ALOT of cornering force in the process...best of both worlds.

Chris

 

thats exactly right..... i dont know where ppl come up with this "no rear sway bars destroys handling" myth. in SRX7 (1st gens), it is recommended that you start with NO rear sway bar. the reason... its easier to drive a car that tends to understeer rather than one that tends to snap into oversteer. and on the street, i doubt anyone would notice with, or without.

--eric

 

i admit it chris. my front pogo's due to shot shocks and i think my rear steer bushings are looser than jenna jameson.

 

DOH! But just like your car Jenna still looks hot and I'd like to have it no matter how many miles are on it!

Chris

 

Sounds good, Steve. I'll give you a call after the Holiday. Just let me know when you are ready to upgrade your wheels . Anytime I can save some coin is a time to spend more on the motor.

 

no sway bar = stiff springs
stiff springs = lower traction potential