Camber angles while steering

[Dash]

And i'm back! Hah.

Got another question(s) to throw out there.

I've seen the term " camber thrust" thrown around, but haven't been able to pin down a good definition. Any help?

Also, when cornering, what do you want your inside wheel to do camber-wise? Pretty much all i've been told ( or read ) is to not let it get positive camber. Is this a true fact?

Lastly, what does KPI have to do with the car handling. I know it effects scrub, which effects driver feedback and steering force, but what are some ballpark ranges for degrees, or inches of scrub?

Thanks for all the help guys, you have been very informative! http://fsae.com/groupee_common/emoticons/icon_biggrin.gif

[Dash]

And i'm back! Hah.

Got another question(s) to throw out there.

I've seen the term " camber thrust" thrown around, but haven't been able to pin down a good definition. Any help?

Also, when cornering, what do you want your inside wheel to do camber-wise? Pretty much all i've been told ( or read ) is to not let it get positive camber. Is this a true fact?

Lastly, what does KPI have to do with the car handling. I know it effects scrub, which effects driver feedback and steering force, but what are some ballpark ranges for degrees, or inches of scrub?

Thanks for all the help guys, you have been very informative! http://fsae.com/groupee_common/emoticons/icon_biggrin.gif

[exFSAE]

Camber thrust shifts the Fy vs SA curve left and right. It's a horizontal displacement. Sometimes also provides higher peak Fy.

What do you want your inside wheel to do when cornering? That depends on the tire. Check your tire data. You tell me.

KPI does change your scrub radius, and also effects how much camber gain you get with steering. No such thing as a ballpark range. Depends on tire, spindle offsets, etc.

[woodsy96]

The way I like to think of camber thrust is that a cambered wheel deforms from a cylinder to a truncated cone (as the effective radius of the tire now varies along the spindle axis), and therefore prefers to go around corners. There are some good plots in RCVD to show its effects better, but of course different tires will react differently.

Designing KPI also requires consideration of your caster angle, and how in combination they affects your camber in steering. Most of the stuff I've read says that KPI is bad, and to tune it out if you can.

[Yellow Ranger]

what tire are you planning on running? a particular tire we've used, it makes little difference what your camber is (about .5%) at higher slip angles, but the camber thrust helps overall Fy in the linear ranges of the tire. So it seems like, if all you were looking for was max Fy, you'd want a car that has like -5 degrees of camber, but then your tires probably wouldnt last too long, or do too hot in long performance...

and that's the beauty of KPI, caster and steering

[Dash]

Thanks guys for clearing that up.

Last years suspension guy turned into tire data guy this year. After talking with him, i think i've got it figured out.

^_^