Why would I use positive camber?

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DiogoBrand
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Location: Brazil

Why would I use positive camber?

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I recently bought a used Civic and took it to an alignment shop. When the front wheels were set to 0 toe they both showed a value of +0,30 degrees in camber. The car and its suspension doesn't show any damage or wear at all, and the recommended values were between +0,14 and +0,54, so it wass pretty much right in the middle. I don't remember what were the values for the rear wheels, though.
My question is: Why would the car have a positive camber value? From my little knowledge of the subject I can't think of any significant benefit.

Greg Locock
Greg Locock
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Joined: Fri Jun 29, 2012 11:48 pm

Re: Why would I use positive camber?

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Maybe for limit handling? This would give more limit understeer. It's probably worth pointing out that modern tires are much less sensitive to camber than old crossplies, so a lot of racing lore is less applicable. Roughly speaking a modern tire has a camber thrust about 20% of the cornering compliance, so your 0.3 degrees of camber would have about the same effect as 0.06 degrees of steer on that wheel, not a whole damn lot. What sort of suspension is it?

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DiogoBrand
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Joined: Thu May 14, 2015 6:02 pm
Location: Brazil

Re: Why would I use positive camber?

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McPherson at the front, double wishbone at the back.
I also think it's to create understeer. Understeer is safer for everyday use so I think most manufacturers try to create it one way or the other on cars that aren't meant to be sporty.
Either that or trying to prevent uneven wear on the inside shoulder.

NL_Fer
NL_Fer
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Joined: Sun Jun 15, 2014 8:48 am

Re: Why would I use positive camber?

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Does it change to negative camber, once cornering load presses the outer side of the car down ?

Mchamilton
Mchamilton
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Joined: Sat Feb 26, 2011 4:16 pm

Re: Why would I use positive camber?

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What year civic is it? Eg/ek/ej aren't mcpherson strut on the front, they're double wishbone essentially so they have good camber gain under load.

Greg Locock
Greg Locock
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Joined: Fri Jun 29, 2012 11:48 pm

Re: Why would I use positive camber?

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They switched to the cheap suspension a few years back. That means that when it rolls by 4 deg per g (or so), all of that will be seen as positive camber on the outside wheel, so a few tenths of static are neither here nor there.

gruntguru
gruntguru
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Re: Why would I use positive camber?

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Likely it runs a fair bit of caster so the positive camber reduces to negative on the outside wheel - most significantly in tight radius (slower) turns. Result is the car is more stable (understeerish) in high speed, large radius turns but still agile when needed.
je suis charlie

Tommy Cookers
Tommy Cookers
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Joined: Fri Feb 17, 2012 3:55 pm

Re: Why would I use positive camber?

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roads have positive camber
so the big thing c. 1911 was the race Mercedes positive camber rear axle (front axles were always positive camber)