No rear sway bar = better grip?

[iitywygms]

I heard that removing the rear sway bar on a s13 can result in better performance for grip racing. Anyone done this? Did it help or hurt?I currently run progress sway bars front and rear. The front is at the stiffest setting and the rear at the softest. I have been trying to keep the rear of the car from swinging around all year at the track but could never totally eliminate it. (Yes that's correct, I don't want to drift)What are your opinions?Current setup is. Spotlines with tokico blues and all the usual suspension goodies, fender braces, strut bars, etc etc.

[sultan]

i assume you don't have the stock rear anymore?

[Z Style]

Yeah, maybe go back to a stock one or just unhook it to try it.

[iitywygms]

The stock one is gone. I am going to un-hook the one I have eventually. I just wondered if anyone had done this and what it was like.

[Chukidori]

I took my stock rear sway bar before i put white line rear sway bar on to see the effect of removing it, and the effect of the white line bar.

With no rear bar I did notice better turn in. I do believe its because during the initial Turn in the rear rolls and sacrifices enough grip to where they arent "pushing" the front tires through as much on entry.

But ive found with my white line rear bar..I have more "neutral" handling mid corner


Modified by Chukidori at 5:33 PM 10/19/2008

[spooled240]

People tell me that you will have better grip with out a rear sway bar with the IRS setup, but after I put my aftermarket sway bar on (28mm tubular) I thought the car gripped a lot better in high speed cornering that's for sure.

Theoretically, I think you can have a lot of grip with out a rear sway bar but you'll definitely need some stiff suspension and some wide tires.

edit: a little off-topic, but a vlsd will also greatly improve grip in cornering.

[nissanman04]

The reason why people notice improved handling w/o a rear sway bar is that our chassis tends to lift the inside rear during heavy (steady state) cornering, leaving only one tire with all of the rear load, resulting in less grip. Removing the sway bar allows the inside wheel to stay on the ground, giving more overall grip. However, the lack of a rear sway bar will hurt performance during transitions since there is less resistance to body roll. As is usually the case in motorsport, it's all about compromises. I've been running with a whiteline sway up front and a stock rear, and I am pleased with the current balance of the car.

[iitywygms]

People tell me that you will have better grip with out a rear sway bar with the IRS setup, but after I put my aftermarket sway bar on (28mm tubular) I thought the car gripped a lot better in high speed cornering that's for sure.

Theoretically, I think you can have a lot of grip with out a rear sway bar but you'll definitely need some stiff suspension and some wide tires.

edit: a little off-topic, but a vlsd will also greatly improve grip in cornering.

What is a irs setup? and yes, I do have a vlsd, probably the best thing I put on the car.

[hai1206vn]

IRS =independent rear susp. I've been running autox without a rear bar and i can tell the rear rolls a lot even with stiffer springs (5kg, not that stiff though). But the grip in mid corner and at exit feels a lot better.

[iitywygms]

IRS =independent rear susp. I've been running autox without a rear bar and i can tell the rear rolls a lot even with stiffer springs (5kg, not that stiff though). But the grip in mid corner and at exit feels a lot better.

That is exactly where I have problems. When I would start the corner exit and hit the gas the rear would start to slide out. Next year I will run no sway and get some coilovers. Stance I think. Hopefully not to stiff for a daily. And some new tires.

[OchnofConcrete]

However, the lack of a rear sway bar will hurt performance during transitions since there is less resistance to body roll.

transitions are a major part of racing. noticable in the s-turns, and any other turn when you're clipping the inside track curb

[OchnofConcrete]

i'm not very familiar with highclass suspensions.. but when you think about it.. body roll and grip are big factors of performance on roadtracks. what would be nice is to have chassis suspension and road suspension that are independent.. that way your weight doesn't shift during transitions but your tire grip is still spongy and sorta slumps on the road no matter the manuver. not really doable unless your body had suspension onto the chassis. which is just wierd and over done and outrageously expensive.

[hai1206vn]

When I would start the corner exit and hit the gas the rear would start to slide out.

Still, even without the rear bar you cannot slam on the gas. Smoothness is key.

And some new tires.

Definitely. Every other upgrade you can dream of doing to the suspension is worthless without proper tires. I made that mistake. No all season of any grade (even max performance AS) for grip driving

[iitywygms]

OchnofConcrete, I feel the best setup to do like you said is soft springs with stiff bars. I am sure others will disagree but that is what I am running.

hai1206vn, That is true. I am still new at this stuff and always want to floor it when exiting. I am getting better. I am surprised that a normal kade can put enough power down to make me loose traction, especially at higher speeds.The next step will be federal 595rs 245x40x17

Anyway, I guess it will be fun to remove the rear bar and see what happens.

[spooled240]

i'm running soft springs with stiff bars and my car still has some body roll in hard cornering I want some stiffer springs or better yet some coilovers.

As with the inside wheel lifting in cornering, that will happen with coilovers as well, think about people with coilovers "three-wheeling" it in driveways, the coilovers don't let the wheels hang down much at all.

Just from my experiences, I prefer a rigid and stiff setup without a lot of weight transfer. It' probably not optimum, but rigid cars are a lot of fun and more responsive and predictable.

[nousablenames133]

the purpose of a sway bar is to increase the roll resistance without changing the wheel rates in longitudinal load transfer. They also serve as an easy way of adjusting over/understeer characteristics. how stiff the bars need to be is dictated by the roll resistance of the rest of the suspension. in theory stiffer suspension means softer anti roll bars, but if you increase the suspension stiffness to the point where you dont need anti roll bars your longitudinal compliance will be too stiff. a con to anti roll bars is reduced suspension independence. if you hit a rumble strip, or a bump on one side only, deflection will still be transferred to the other side.

in theory removing your rear sway bar will increase traction in corner exit, but whether it'll increase overall performance is still questionable. i can't say for sure because i'm not familiar with tokico dampers or the spotline spring rates. i'm going to guess you're going to want to keep some sway bar on, whether it's the oe one or your whiteline one.

not to insult your driving capability, but especially since you are running a stock powertrain, i'm going to guess you need to learn better throttle modulation. one of the things i think jackie stewart told james may when he was teaching him to drive was you never get on the gas pedal until you know you wont need to take it off.

[1mansho]

I have a tanabe rear sway and stock fronts and after putting them on, i felt a significant reduction in roll and with my welded diff resulting in alot of grip. I can't even get my car to oversteer!

[LOVERboy]

As with the inside wheel lifting in cornering, that will happen with coilovers as well, think about people with coilovers "three-wheeling" it in driveways, the coilovers don't let the wheels hang down much at all.

Just from my experiences, I prefer a rigid and stiff setup without a lot of weight transfer. It' probably not optimum, but rigid cars are a lot of fun and more responsive and predictable.

[Chukidori]

I know this sounds crazy..But OP, buy some adjustable TC rods and play with your caster..Most street cars especcialy 240s have high caster angles. More caster will tend to transfer more weight across the front of the car..its the angle of the steering axis forward or rearward when viewd from the side. by adjusting the tc rod you are pushing the wheel hub back, or forward.

[Frogman240]

I have a no rear sway bar but have the stock front. I have never really experienced body roll during any driving style. My set up on suspension is quit stiff though I have Megan Racing coilovers and all the adjustable pieces in the rear except the traction link. I also have a VLSD but it has about 250,xxx miles on it so i don't know how effective it is (I've heard that they commonly wear out with high mileage) I think my coilovers are what prevent the body roll, yet i do experience a mild slide during very aggressive turning. IMO if you want to eliminate body roll coilovers are the way to do it.

[iitywygms]

I know this sounds crazy..But OP, buy some adjustable TC rods and play with your caster..Most street cars especcialy 240s have high caster angles. More caster will tend to transfer more weight across the front of the car..its the angle of the steering axis forward or rearward when viewd from the side. by adjusting the tc rod you are pushing the wheel hub back, or forward.

So I should decrease the caster... hmm, I will have to give this a shot.I would much rather do this and keep the rear sway bar.

[Chukidori]

Yeah, neutral caster brings the steering axis IN LINE with the wheel hub and thus the contact patch.

less caster will make it more "darty" on turn in as the contact patch remains flatter, but you will get less camber gain during sustained cornering and MAYBE you might experience more push later in the corner...Which is why id keep the rear sway bar.

Higher caster brings the wheel forward more..and this lets the wheel 'caster around" like a shopping cart wheel..and as a side effect, you can actually GAIN camber in the front wheels as you turn more but it makes it more sluggish

[iitywygms]

Yeah, neutral caster brings the steering axis IN LINE with the wheel hub and thus the contact patch.

less caster will make it more "darty" on turn in as the contact patch remains flatter, but you will get less camber gain during sustained cornering and MAYBE you might experience more push later in the corner...Which is why id keep the rear sway bar.

Higher caster brings the wheel forward more..and this lets the wheel 'caster around" like a shopping cart wheel..and as a side effect, you can actually GAIN camber in the front wheels as you turn more but it makes it more sluggish

Thanks for the info. I wish I had more track time left but we are finished for the year. I know stock caster is 6.0 - 7.5. Do you have a recommendation for a good starting point for caster?

[S13Teddy]

I have no rear sway bar and I took it drifting. Didn't notice a single difference.

Less bolts for me to take off when I break subframes.

[iitywygms]

Hey Chukidori

What do you suggest for caster? (Ballpark)