Ever tried removing the front swaybar?

[Loren]

Before I tell you how well it worked... raise your hand if you think autocrossing without a front swaybar sounds goofy.

[Sabretooth]

hmm, prolly felt like you were driving on really really underinflated tires?

[kngrsll]

i would think it would suck? but i dunno.

[1NZYaris1]

[Loren]

Well, with an otherwise stock suspension, you'd both probably be exactly correct.

However, I don't have a stock suspension. I have a 23mm rear swaybar (thanks, Garm), and I have rear spring rates that are nearly double the front. (4kg/mm front, 7kg/mm rear)

As it turns out, still have considerably more roll resistance than stock, even with the front bar removed. In fact in normal street driving, I hardly noticed the difference when I removed it.

Today, I got the opportunity to autocross the car without the front bar for the first time and I really liked it. I've been stiffening the rear of the car to tame the understeer and the inside wheelspin when accelerating out of a turn. I generally like the car to be right on the verge of oversteer, such that if I lift throttle in a turn, the back end will come around. Not because I want the back end to come around (I really don't use that technique much), but because that balance allows the greatest throttle application while turning. Even with the stiffer rear springs and the large rear bar, I still found that I had to crank the rear shocks to near full stiff to achieve that goal, and even then I still got more inside wheelspin than I wanted.

With the front bar removed (okay, I really haven't actually removed it, I just removed an end link for this experiment... the dead weight will come out when I get a chance, though), I didn't experience any inside wheelspin today at all. I'm not saying it was like adding a limited slip, I still couldn't go full throttle everywhere... but that inside tire stayed planted. Stiffening the rear shocks to about half-stiff made it even better, and that was all it took to get the rear end to step out. No need to go full stiff on the rear shocks.

Why does it work? It's quite simply the way swaybars work. When you're hard in a turn, the outside front suspension is compressed. That wheel is way up in the wheelwell. What does the front swaybar do? It is a connection to the other front wheel. It pulls UP on that wheel... the one that likes to spin wildly when you want to accelerate out of a turn. So, removing it, allows that inside wheel to stay down on the pavement where you need it!

Side effect of my latest round of rear suspension stiffening and front suspension softening has resulted in a lot more REAR inside tire lift than before... but, aside from generating a lot of comments from bystanders, that's a GOOD thing. Weight that ISN'T on the rear IS on the front, and a FWD car's problem is with getting the FRONT to grip, not the rear.

Now, this isn't for everyone. But, if you've got a coilover suspension (or at least adjustable shocks) and a big rear bar, consider it another tool in your arsenal for improved autocross performance. Don't be afraid to think outside of the box... you just might find something that works!

[1NZYaris1]

Makes a lot of sense

[SailDesign]

Originally Posted by Loren

Before I tell you how well it worked... raise your hand if you think autocrossing without a front swaybar sounds goofy.

Without even reading the rest of the thread, I know it works, if you're the right person. A fellow called Richard Shine has a tuning shop up in New England, and he has been removing the front bars from VWs for years. Some love it, some hate it, but either way it works. More power available to the driven wheel.

[Loren]

Hey, I've heard of Shine racing! And I know for sure I didn't invent the notion of removing the front bar from a FWD car. Much older and wiser people than I have been doing it for decades!

PK, like every other part of your suspension, the front swaybar (or the lack thereof) is a part of a system. If you take a stock Yaris and JUST remove the front swaybar, it's gonna suck. Would probably put down power coming out of a turn, but would suck in all of the other ways that you mentioned.

But, like I said, the rest of my suspension is NOT stock. I've done other things that counter the negative effects of removing a front swaybar. The roll stiffness that I have in the rear more than takes care of any "wobble" at high speeds (or any other speeds). I can adjust the sharpness of the steering with the front shock stiffness. With the shocks near full soft (where I've kept them for street driving), the steering response is a little more sluggish than it was, though probably no more than stock, and certainly not objectionable.

There was a tight slalom (5 cones at 50') on today's course and with just a little bit of front shock stiffness (about 1/4 stiff) I didn't have to put any thought into driving it at all.

Part of today's course was also 1.5x around a 200' skidpad, sweepers are NOT a problem.

This is the easiest thing in the world to experiment with. If you think you MIGHT like it, or you're just curious... remove an end link. All of your questions will be answered.

[Loren]

Originally Posted by PK198105

p.s what are you using as suspension mods if i may ask?

You could ask... or you could just read the 6th post in this thread.

[Loren]

The spring rates are actually more relevant than the make/model, IMO. If you're the kind of person who's going to order a coilover kit without knowing the spring rates that it comes with... you probably shouldn't even be reading this.

That said, I have a K-Sport Kontrol Pro coilover kit. Completely unmodified except for the rear springs. Pretty basic stuff, but it gets the job done. Alignment is presently at about -2.5 front and -1.5 rear for camber, zero toe in front and stock toe in the rear. Ride height isn't very low at all... maybe 1.5" lower than stock.

[cali yaris]

pretty cool, and like the power steering experiment, very easy to try out and put back.

Actually removing the sway bar is a lot more involved, I hadn't thought of simply disabling it. easy-to-undo experiments!

[kngrsll]

cool write up... what autox did you go to? i had planned on going to the Roebling Road Buccaneer event but i totally forgot about until Sunday. :(

[Loren]

I was at a St Pete area event with my local club: http://wedrivefast.com/

There are about 5 autocross clubs in this area that I can think of.

[kngrsll]

i'm jealous!

So i think may try this out at the next event. although my set up is quite different, so i am not sure how it will go. I have some spring rubbers (98 lbs!) that i can try out as well.

Thanks for the tip!

[scape]

funny how this is a working idea, and yet they sell front sway bars ;d
have you thought about running lower profile tires in the rear only? just a thought i've been having lately

[Loren]

They sell front swaybars because people will buy them. (and you won't make any money by telling people to remove their front swaybar)

Nope, never considered running lower profile tires in the rear vs the front. The thought never crossed my mind. Even if there were some benefit to doing so (I sure can't think of one), I like having the same size on all four corners so that I can rotate the tires when I need to.

[scape]

good points

[Loren]

BTW, just to prove that I used to be young and dumb too... the first performance part I bought for my Saturn after I started autocrossing in 1996 was a front swaybar. Why? Same reason everybody else thinks they want one for their Yaris, to reduce body roll... and because it was available!

I spent the next 4 years modifying AROUND that mistake because I was too stubborn to remove that part that I'd paid good money for. I ended up with a good handling car, but it was far more difficult than it should have been. If I was smart, I'd have fitted the smaller front bar from an SC1 onto my SC2 instead of fitting a stiffer bar. (the S-series suspension design uses the front swaybar in an unconventional way, you can't drive the car without one)