I-man
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| posted on 21/1/09 at 09:52 PM |
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Calculating camber gain
Question about camber gain;
I read somewhere on this forum the the Lotus Elise has a camber gain of 0.31 degrees per inch of travel on the front suspension. Can someone tell me
if this through out the full travel? or is it for only the bump or only the rebound.
I'm doing the drawings for my wishbone suspension and I have a bump of 2 inches with a camber gain of -1.33 degrees and rebound of 3.5 inches
with a camber gain of 1.14 degrees. Would this be seen as total camber gain of 2.47 degrees per inch of travel or something else?? By the way
I'm guessing the body roll is about 3 degrees and the ride height is about 5 inches.
Also has anyone got any ideas on what camber gain I should be aiming for? (for the total, just bump, and just rebound).
I-man
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brianthemagical
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| posted on 22/1/09 at 09:54 AM |
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Have you mixed up your plus and minus signs or are you loosing camber in bump?
What your after depends on many factors, ideally you want the wheel angle in roll to be perfect, so sort that first, and then just comprimise on the
bump gain. You should also be looking to keep the roll centre quite stable if poss.
As to how much camber you need, depends on the car and use, i.e, wide slicks need less, high profiles usually need more.
HTH
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minitici
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| posted on 22/1/09 at 10:02 AM |
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If you know your pick-up points and wishbone lengths use this handy suspension geometry calculator on-line.
Calculator
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MikeRJ
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| posted on 22/1/09 at 11:48 AM |
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quote:
Originally posted by brianthemagical
Have you mixed up your plus and minus signs or are you loosing camber in bump?
Looks right to me, he is gaining more negative camber in bump, and losing it in droop.
I suspect any number you see for camber gain will be an average, since a typical double wishbone system will not give a linear change over the full
suspension movement.
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hughpinder
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| posted on 22/1/09 at 01:02 PM |
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I have some data for a cateringvan SVR:
30mm rebound = +.7deg, 60mm +1.2
30mm bump -1.0, 60mm -2.3
roll -5 degrees camber angle -3.5
-2.5 -2.3
0 -2
+2.5 -.2
+5 1.0
The same source has a few parameters I'm not familiar with which I would quite like to understand - "anti dive %" and
"ackerman %" - I didnt realise these had %- just you had them or not - anyone know anything?
Regards
Hugh
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brianthemagical
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| posted on 22/1/09 at 06:40 PM |
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(Quote) Looks right to me, he is gaining more negative camber in bump, and losing it in droop.(quote)
Good point, i was confusing myself.
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ettore bugatti
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| posted on 22/1/09 at 07:35 PM |
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http://www.superseven.se/Casim/casim_top_page.htm
Nice software
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I-man
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| posted on 22/1/09 at 08:43 PM |
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Thanks for the input so far..
What I also noticed about he Lotus Elise was the rear camber gain is 0.45 degrees per inch where as the front is 0.31.
Why is the rear got more? Any body know?
My guess is the heavier rear end (with engine) and higher roll center requires it.
I have used software to help position my mounting points etc and plot the camber gain. I can change the mounting positions and wishbone lengths and
angles to what I want. The hard part finding out what i want...or what would make the car handle correctly.
I-man
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kango
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| posted on 25/8/10 at 10:20 AM |
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It must be a "How long is a piece of string" question, because I have red most of the threads on camber gain and no body has mentioned
it.
What is the ideal camber gain (Front/Back) for a light weight race car such as a 7?
I am designing my own uprights so the sky is the limit and it will only be used for track racing.
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Frosty
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| posted on 25/8/10 at 02:30 PM |
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quote:
Originally posted by kango
It must be a "How long is a piece of string" question, because I have red most of the threads on camber gain and no body has mentioned
it.
What is the ideal camber gain (Front/Back) for a light weight race car such as a 7?
I am designing my own uprights so the sky is the limit and it will only be used for track racing.
I don't think there really is such a thing as "idea camber gain" since the amounbt of dynamic camber gained it is ultimately
affected by the weight of the car, and the spring you choose to run.
Obviously if the car ends up running very firm, more camber gain would probably be desirable since the car will travel less in bump.
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