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Toe in/out Camber and Caster ?'s FB

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Old Jun 7, 2013 | 02:13 PM
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Toe in/out Camber and Caster ?'s FB

My questions are about the effects of various alignment choices. I realize what the effects of toe out and negative camber. I am not certain of the effects from caster adjustments or Toe In. Would a team calculate the tracks number of and degree of corners vs. straight away lengths? Obviously these adjustments often are the difference between a winning or struggling car. Can some of you please offer any advice or knowledge in these areas in respect to the FB

Last edited by Adam12A; Jun 7, 2013 at 02:26 PM.
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Old Jun 7, 2013 | 02:34 PM
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front toe in is not an area usually used on any car. At most a car runs square and most folks run toe out in front. More = more turn in under braking and dead pedal, but you scrub straight line speed the more you run and also the car becomes less stable in a straight line.

Toe in in the rear tends to stabilize a car and give more predictable, and you could argue better, turning on the way out (under throttle)

Some guys (usually FWD guys) will run toe out in the rear to improve turn in, but it makes the car less stable. Many guys run square. Some run toe in. It of course depends on the track and the chassis.

Though i rarely mess with caster it supposedly mostly changes the way a car feels to a driver. Less caster is somewhat unpredictable and aggressive some say more responsive and usually more is considered easier to drive, but not necessarily faster. You almost always want caster even side to side or you will get a pulling sensation in the wheel.

Alignment has so many variables, tires, car, track, weight, etc... there is no one way to approach it. It almost always starts with a baseline, and you work from there based on the stopwatch and driver feedback as well as tire pressures and temperatures. Looking at track geometry and making alignment choices from there is not the way any teams really go about it.
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Old Jun 7, 2013 | 03:46 PM
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Alignment has so many variables, tires, car, track, weight, etc... there is no one way to approach it. It almost always starts with a baseline, and you work from there based on the stopwatch and driver feedback as well as tire pressures and temperatures. Looking at track geometry and making alignment choices from there is not the way any teams really go about it.[/QUOTE]
Thanks for the response.
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Old Jun 7, 2013 | 03:50 PM
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I am also wondering about people who run different settings from left to right. Would that decision be based on the direction of the track clockwise vs, counter which would make more corners in one direction over the other?
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Old Jun 7, 2013 | 05:59 PM
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Like Lobster said, caster helps a lot with steering feel, and self centering. Caster also creates camber when the wheels are turned. So some of the caster decision is based on how far you have to turn the wheel to make all your corners, and how much the chassis will pitch/roll during the corner (related to springs and anti-roll bars).
The FB has been around long enough though that the setting should be pretty figured out by now. So hopefully someone with actual FB racing experience will chime in and just tell you what numbers to run (ballpark).
Good luck!
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Old Jun 7, 2013 | 10:38 PM
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Originally Posted by Adam12A
I am also wondering about people who run different settings from left to right. Would that decision be based on the direction of the track clockwise vs, counter which would make more corners in one direction over the other?
Yes, if you set up your car for a specific track, more corners go one way than the other, so you'll setup your car to have more camber on that side and less on the other so in those turns the inside wheel is flatter than it would be with more camber...

Camber is the only thing that some people vary per side though, and unless you're super serious, I wouldn't worry about it.
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Old Jun 7, 2013 | 11:19 PM
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From: https://www2.mazda.com/en/100th/
Originally Posted by Adam12A
I am also wondering about people who run different settings from left to right. Would that decision be based on the direction of the track clockwise vs, counter which would make more corners in one direction over the other?
yes, camber can be different track to track, and also with tire size, and brand.

camber is pretty straight forward, you can set it with the temp gauge.

for toe, start at zero, and then try a little toe in, and a little toe out, part of the game is to figure out what works for YOU on YOUR car.

lastly, try a max castor and minimum castor, and see what happens.
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Old Jun 9, 2013 | 09:03 PM
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On my ITA RX7 too much toe in/out scrubbed speed big time so I would pay close attention to that. Also, an FB has better akerman that allot of other strut cars because they are rear steer. For intance compared to a FOX/SN95 Musang, A mustang needs toe out to work and FB doesn't. On an FB you can get more akerman with the "turn in" style strut spacers from RE Speed and G Force.

Tuning for a particular track varies. When I raced at Gateway in StL I changed ride height left to right - raised the right side and lowered the left side because it was a Roval (road course-oval) It made the car fast and comfortable in the NASCAR turns and it also helped turn 1-2 in the infield. At other tracks settings may be different, you have to experiement and test. In my experience you tune the car to make the most speed in the most common and or important turns at a track.
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