I still think you can disconnect the rear sway, and leave things be but just adjust things with alignment and shocks to get the character you are looking for.

I am running 245F and 275R with 16k f/r and no rear sway with 03 front sway, -3 camber F/R.

I can get the car to understeer/oversteer by adjusting my shocks and gas pedal. I am no expert but you can do alot without going thru and spending more money on new springs.

 

It's my non-professional opinion that sway bars are ways to decrease roll without sacrificing too much ride comfort. Ride comfort isn't exactly a priority for a track car. But remember that nothing is as simple as "this is what you need and this is what you don't" with suspension.

As Turn-R-Us pointed out, there are many possible means to very similar ends.

 

Really simple and funny that the dog pile started on this already.

The roll bar provides relative increase in spring (total) rate in one corner in bump. It provides no increase in relative rate when both wheels bump at the same time. It provides roll resistance at 4th POWER for increasing diameter, so unless you run much stiffer springs you will not have the same effect on roll stiffness (and the eventual slip angle).

The old Chassis Dynamics book has a great chapter on this subject, as does Make Your Car Handle by Fred Puhn. Race Car Engineering and Mechanics by Paul Van Valkenburg (also see his essays in Racecar Engineering).

He is getting rear wheel lift with the bar, and now has (MORE) understeer without the bar. He can stiffen the rear again...lol with springs this time, or he can stiffen the front to get the more neutral feel. Not contradicting anyone's experience here, this is straight textbook.

Obviously adding considerably more spring rate to the rear is going to make the car more succeptible to snap oversteer. I have driven cars like that, and while some of it can be dialed out, it makes our car a real handful.

On the other hand, adding a bigger sway up front...just as Honda did in the CR, gives all of the benefits, without any of the drawbacks. And, probably better turn in as well.

If someone really wants a factual discussion of actual value, look at why the rear is lifting, loss of travel from the rear bar, or too much spring rate relative to the front...

 

I think the purpose of stiffening the rear springs after removing the rear bar is to find a comfortable middle spot. In any case, softening the rear has the same effect as stiffening the front. Since the net effect of removing the rear bar and stiffening the rear springs a little is to soften the rear, mission accomplished.

I'm not sure I understand how stiffer individual springs increases snap oversteer, could you explain that?

Honda also added a wing that is too low by "track" standards.

 

I would not attempt higher rear rates simply to lessen body roll. You'd need a CRAPLOAD of rear spring to influence roll to the point you are looking for.

1st things 1st. There are three phases of a corner: entry, mid and exit. The wheel spin that you're dealing with is on exit and it's a carryover from mid. How does your car feel at mid corner? If you get on a skid pad what does the car do? Usually, a car that gets inside spin on exit suffers from push at mid corner because the rear is so soft.

First, fix the car at mid corner then adjust shocks to suit entry and exit.

 

Hey Terry...here's the justification: Since a swaybar connects the right & left suspension, it reduces roll by leveraging the unloading spring to help lift the compressing spring. The swaybar is trying to compress the unloading spring...and that can cause wheel lift.

The swaybar allows the potential from both springs to be used to control body roll. This allows the car to use softer springs for ride comfort, but still have roll control.

To acheive the same potential with only one spring, that spring has to be much stiffer.

So, if you remove the rsb, you can maintain the roll resistance by increasing the spring rate. Which, as eurotrashdtm mentioned, maks the suspension more independent.

 

[QUOTE=glagola1,Jan 29 2008, 07:30 AM] I would not attempt higher rear rates simply to lessen body roll.

 

Fix it mid corner. If you can't tell me what it's doing mid-corner, then you have some work to do.

 

Exactly. Set springs rates to keep the wheels in contact with the ground around the track, then make up the difference between what you get and your target roll rates with bars. That is how you design a suspension from scratch.

 

Eh, not exactly. There's a whole bunch of math that involves corner weights, motion ratio, and natural frequencies that's supposedly the way to determine spring rates. Don't know much about it besides what I've read though.