what kind of toe setting are the best for cornering with a front wheel car?

The car is primarily used for solo1/2 events. Its an ITR.

Any help would be appreciated.

 

1/16" toe out per side - 1/8" total

 

...and, as I learned this weekend, to encourage the backend to be loose, 0" toe in rear. It'll be a little more twichy, but should rotate easier.

 

Toe In = Understeer.


Right? Is there a general consensus on that?

 

any toe will scrub off straight-line speed because of the added rolling resistance. in SM, the majority of us try to run 0 toe all around because of our limited HP. at my last race i was all over the back of another car, got into a racing incident with his door and my front wheel/fender. this knocked the toe way out of whack, and from that point forward i just couldn't catch him anymore. so whatever you decide to run with, do it as little as possible to keep that speed down the straight.

i'm not sure what honda guys are running, but if anything i would guess they have some toe-in at the front given the way a fwd car is driven.

 

oops, i meant REAR toe-in.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .RJ &raquo;</TD></TR><TR><TD CLASS="quote">1/16" toe out per side - 1/8" total</TD></TR></TABLE>

In front, that is. Except double it. 1/4 inch toe out in front is a little darty but turn-in is great. I like it a lot.

1/8th total out and you won't see as much tread wear on the street, if you're not resetting it between events and daily driving. It seems to be a consensus autox/HPDE alignment, though I couldn't tell you for sure what the national champions are running.

0 toe in the rear is pretty safe.

At this point, it's a matter of taste, but a little toe out in front is a GOOD thing.

-Chris

 

Another note, you'll see everyone is quoting toe in INCHES and not degrees. Degrees would be more "accurate" since it doesn't change with tire geometry/height/etc.

NOTE: If you take it to a shop not used to anything but zero toe, ask for the toe on each side, i.e. (.3 degrees toe OUT on each side in front, NOT .6 degrees total toe out, because "total toe" confuses them. I got twice the toe I was looking for once, whoops! Measured at home to be about a half inch toe out, which is just plain silly.)

https://honda-tech.com/zerothread?id=1061318
or

 

so i'm an idiot. oh well.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tnord &raquo;</TD></TR><TR><TD CLASS="quote">so i'm an idiot. oh well. </TD></TR></TABLE>

Your car is just backwards and underpowered, that's all

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chris F &raquo;</TD></TR><TR><TD CLASS="quote">

Your car is just backwards and underpowered, that's all

</TD></TR></TABLE>

I think thats worse the calling him an idiot!!...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chris F &raquo;</TD></TR><TR><TD CLASS="quote">

Your car is just backwards and underpowered, that's all

</TD></TR></TABLE>

smoked most everyone else in the instructor group at exbl0!

 

thanks alot everyone.

 

Ive always run 0 toe, even on my WRX.
Can someone provide a technical reason for toe in or out? If you cant get your car to handle the way you want or need to tweak it a bit I can understand, but in an ideal situation I dont see how toe is doing anything but slowing you down.

Of course, you guys do drive FWD econoboxes, so maybe you have to use every tool you can for your car to not handle shitty

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by elgorey &raquo;</TD></TR><TR><TD CLASS="quote">Of course, you guys do drive FWD econoboxes, so maybe you have to use every tool you can for your car to not handle shitty </TD></TR></TABLE>

IMO-

You hit the nail on the head.

 

Front toe out will generally make the car react quicker to steering inputs. Toe in has the opposite effect, making the car seem to take forever to react.

Too much toe out will result in tire scrub on straights and will slow you down, so there is a point of diminishing returns.
This doesn't really apply to autocross, where handling will be paramount over a slight loss of speed on a really short "straight."

 

from some old grassroots article:

When a pair of wheels is set so that their leading edges are pointed slightly towards each other, the wheel pair is said to have toe-in. If the leading edges point away from each other, the pair is said to have toe-out. The amount of toe can be expressed in degrees as the angle to which the wheels are out of parallel, or more commonly, as the difference between the track widths as measured at the leading and trailing edges of the tires or wheels. Toe settings affect three major areas of performance: tire wear, straight-line stability and corner entry handling characteristics.

For minimum tire wear and power loss, the wheels on a given axle of a car should point directly ahead when the car is running in a straight line. Excessive toe-in or toe-out causes the tires to scrub, since they are always turned relative to the direction of travel. Too much toe-in causes accelerated wear at the outboard edges of the tires, while too much toe-out causes wear at the inboard edges.



So if minimum tire wear and power loss are achieved with zero toe, why have any toe angles at all? The answer is that toe settings have a major impact on directional stability. The illustrations at right show the mechanisms involved. With the steering wheel centered, toe-in causes the wheels to tend to roll along paths that intersect each other. Under this condition, the wheels are at odds with each other, and no turn results.

When the wheel on one side of the car encounters a disturbance, that wheel is pulled rearward about its steering axis. This action also pulls the other wheel in the same steering direction. If it's a minor disturbance, the disturbed wheel will steer only a small amount, perhaps so that it's rolling straight ahead instead of toed-in slightly. But note that with this slight steering input, the rolling paths of the wheels still don't describe a turn. The wheels have absorbed the irregularity without significantly changing the direction of the vehicle. In this way, toe-in enhances straight-line stability.

If the car is set up with toe-out, however, the front wheels are aligned so that slight disturbances cause the wheel pair to assume rolling directions that do describe a turn. Any minute steering angle beyond the perfectly centered position will cause the inner wheel to steer in a tighter turn radius than the outer wheel. Thus, the car will always be trying to enter a turn, rather than maintaining a straight line of travel. So it's clear that toe-out encourages the initiation of a turn, while toe-in discourages it.

 

The original poster specified Solo 1 <u>and</u> Solo 2, and I am not sure the same suspension settings would work best on a DC2 ITR in both kinds of events.

For example, if you are on a track where you might reach relatively high speeds (130-140) before threshold braking, many of us find that slight static toe-in on the rear helps us control the car better when the rear end hikes up.

Since the car tends to go positive camber and toe out when the rear end goes up under braking, it helps maintain a little more control of the car. If he's in a situation at BSR Seat Time or NASA Group 3/Group 4 then it's possible someone could actually be beside him when thresold braking from high speeds, and the extra control might be appreciated.

On the other hand, I am old and slow...so what do I know.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tnord &raquo;</TD></TR><TR><TD CLASS="quote">smoked most everyone else in the instructor group at exbl0! </TD></TR></TABLE>

*cough* With some notable exceptions. (thanks again for the tool and windex loanage, man)
-Chris

 

What would make the car more stable at high speeds. My cars seems to be very twitchy at higher speeds.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDM Factor &raquo;</TD></TR><TR><TD CLASS="quote">What would make the car more stable at high speeds. My cars seems to be very twitchy at higher speeds. </TD></TR></TABLE>

Slow down.



IMO-- Stiffer springs all around. Less toe out in front. Different tires. Fix the rear toe (either zero toe or toe in a little).

Is this just under braking, or overall stability? Under braking the rear will lift and toe-out... stiffer springs help. Also brake bias can change the twitchiness.

 

I'm running 10k in the front and 12k in the rear. It's mostly in a straight line, under braking it's okay but im sure if I corrected the straight-line problem it would be a lot more stable under braking as well. The toe is a 0 in the rear, im not sure what it is in the front. I'm running on Hoosier R3S04's.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDM Factor &raquo;</TD></TR><TR><TD CLASS="quote">What would make the car more stable at high speeds. My cars seems to be very twitchy at higher speeds. </TD></TR></TABLE>

try running 1mm of toe-in in the front and rear. That will stabilize the car at speed. Also run no more than -1.5 degrees of camber. I assume you're talking highway here -- if track then the first thing to do is check alignment. Even with 0 toe your car should never be unstable at speed. That's just scary.

 

It's not that it's unstable it just feels very twitchy.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDM Factor &raquo;</TD></TR><TR><TD CLASS="quote">It's not that it's unstable it just feels very twitchy.</TD></TR></TABLE>

How long have you been driving? (sorry, don't know your history). It could just be a confidence thing, I know I felt a bit of that.

Could be aero. How fast are you talking about? 120 MPH?

How old of a car, maybe a torn bushing somewhere in the rear?