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Talking camber and low :)

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    Talking camber and low :)

    Originally posted by domesticated View Post
    It's about 3" front


    Not really attainable to get that much in the rear just from lowering.
    This post from domesticated prompted me to bring up something that had crossed my mind a while now. (domesticated: weren't you lowered over 2 inches without a camberkit? I could be mistaken)

    Now I'm no engineer, or geometrist (geometricist) I don't even know how to read this chart ^^, I'm just coming off the top of the head here, but I was pretty ok in physics and maths in school (albeit high school). That word geometry I've seen posted a lot when talking about lowering the CB, and I wonder if people can really claim full understanding of the geometry of the CB front suspension and just go "throw a spc ball-joint in there..." and.... the geometry is back to stock Because from poking around under there I've realized how much of a jenga act the whole thing really is (As well as the beauty of engineered balance, where a number of small components can dissipate the pressure from tons of metal bouncing around while suspended inches from the ground) For instance, there's nothing holding your wheel on to the car but the bearings. I've looked.

    Suspension polled as the 'most misunderstood concept' in 'tuner world', so I take that to mean most people think they understand it, and so frown on the others.

    I think a lot of people think the geometry of the suspension is like a parallelogram, with one long side moving up and down, and the other long side motionless in relation to the road (if your bushings are good), when actually things are moving in arcs rather that straight lines, with multiple pivot points.

    I'm going to draw some diagrams to explain myself.

    #2
    yeah, most people have difficult time understanding vectors, thus explanations have to be reduced to 2D free-body diagrams to simplify the concepts. In the physics world, complete understanding is a must. In the engineering world, whatever meets the specs, haha.

    And because not many know, they're afraid to stray from what they do know... springs, struts, anti sway bars. some don't even know how anti-sway bars work. or the benefits of a wider track width and write it off as related to stance and nothing to do with performance.

    once you change something, change a part, you're never gonna have the stock suspension geometry anymore, because you aren't using stock suspension anymore, unless it was for direct replacement. As such, you'll have new handling characteristics the more you change, which you'll need to learn and understand so you can drive your car. That's why I always warn people who drive my car to take it slow and understand how it drives, because it doesn't drive like stock. And the H&R sticker you get when you buy the H&R suspension kits also say the same thing, once you modify your suspension it will handle differently from stock and you must re-learn how to drive your car with the new equipment.

    so when people say "back to stock", its not really ever gonna be unless you literally go back to stock... you can have "stock" numbers in one area (camber) but the rest will change ever so slightly. kinda like the butterfly effect.
    Last edited by P5ylance; 08-13-2015, 06:36 PM.
    blackROSE Member, with a focus on VIP Style

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      #3
      I'm looking at geometry as arcs, angles and pivots

      Diagram 1: Honda's design (at a standstill, at stock height)


      Pivot A: Anchor bolts to control arm bushings (positioned with strut mount lined up between them)

      Pivot B: Knuckle to Upper ball joint (at determined angle)

      Pivot C: Frame to Lower control arm bushing

      Pivot D: Strut fork to Lower control arm bushing

      Pivot E: Knuckle to Lower ball joint

      i and ii : axle joints

      iii : axle to wheel bearing

      Diagram 2: Honda design (maxed out. either going over bumps, going down into sudden dips, or lowered by using shorter springs/struts)

      Look at that tire, it looks like a old sneaker of a guy who walks on one side of his foot. (Hope his toe was in line )get it..toe. Probably not, probably twinkle toed than a mug. moving on

      Diagram 3: Lowered with adjustable ball-joints

      Thing to remember is that it is pivot A that moves (up and down) squeezing Pivot B in toward the car (while i and ii flex to compensate). Pivot B's arc is now substantially larger than Honda's original designed arc, not to mention it's higher, so the car will meet it quicker and easier. Im not saying good or bad, but the geometry has changed.

      Diagram 4: Lowered with adjustable anchor bolts



      You've introduced a whole new pivot point (F) here. While Pivot A is moving up and down, the uca is swinging on pivot F. Whether good or bad, the geometry has changed, a lot. (thinking of the stress on the metal between Pivots A and F explains to me why bushings go and bolts come loose on these. The tightening bolt of the camberkit does a lot here. ) Either way the geometry has changed.

      Diagram 5: Lowered with original geometry (Shorter Knuckle to match shorter springs/struts)

      that's just my theory, correct me if I'm wrong



      Just saying, if you're going to flame someone on "improper lowering", please let it be based on Tire wear and Tire Grip, and not "messing up the geometry".

      Like I said I'm no expert, but it seems to me that having camber when lowered is actually NOT changing the geometry of Honda, and adding a camberkit is what changes the geometry to fit our extra-Honda purposes.

      I didn't mention other factors, like struts/springs/bushings used as well as alignment. Just about geometry (arcs, angles and pivots)

      Comment


        #4
        Originally posted by P5ylance View Post
        yeah, most people have difficult time understanding vectors, thus explanations have to be reduced to 2D free-body diagrams to simplify the concepts. In the physics world, complete understanding is a must. In the engineering world, whatever meets the specs, haha.

        And because not many know, they're afraid to stray from what they do know... springs, struts, anti sway bars. some don't even know how anti-sway bars work. or the benefits of a wider track width and write it off as related to stance and nothing to do with performance.

        once you change something, change a part, you're never gonna have the stock suspension geometry anymore, because you aren't using stock suspension anymore, unless it was for direct replacement. As such, you'll have new handling characteristics the more you change, which you'll need to learn and understand so you can drive your car. That's why I always warn people who drive my car to take it slow and understand how it drives, because it doesn't drive like stock. And the H&R sticker you get when you buy the H&R suspension kits also say the same thing, once you modify your suspension it will handle differently from stock and you must re-learn how to drive your car with the new equipment.

        so when people say "back to stock", its not really ever gonna be unless you literally go back to stock... you can have "stock" numbers in one area (camber) but the rest will change ever so slightly. kinda like the butterfly effect.
        you said it the way I wanted to.

        In my understanding, they made the car to not handle well, therefore you have to drive it slower, thus it's safer. (It reaches the limit sooner though)

        Wider track, lower center of gravity, less body roll and the limit is extended already (and if everything is firm, better for taking evasive action).

        Now the added strain on the joints may start that butterfly effect on changing out other components.

        But I always say, drive according to what you're driving. That's the safest way to me. (Don't drive stock like its a Grand Prix car, and just because lowered it doesn't mean it's a race car)
        And if it does handle like a racecar...then reckonize, lol

        Comment


          #5
          I'm probably lowered somewhat close to 2". I have yet to find a camber kit that meets my criteria, so I'll deal with the extra camber on my track car.

          As far as the graph. Start at Y=0 on the graph. If you go 2" into jounce (lowered 2") the curve shows about 2" of camber change in the negative direction for the front. You can also tell from this graph that the factory alignment isn't even perfect. Extrapolate for more low.
          Last edited by Domesticated; 08-13-2015, 11:06 PM.
          '93 H22A 5SPD SE - MRT - DIY-Turbo Sizing

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            #6
            Honda made the car to handle very well for what it was supposed to do and during that period in time. It's not a performance car.

            When I first started learning to modeling the suspension, I used triangles as they are MUCH easier to work with but you have one of several points of the suspension geometry with arcs and pivots.

            According to my text, modifying the suspension geometry involves changing:
            Toe
            Camber
            Kingpin Inclination and offset
            Caster angle and mechanical trail
            Thrust line
            Ackermann steering geometry
            Roll Center and Roll axis
            Anti-Dive and Anti-squat

            "Messing up the geometry" is subjective as it depends on the person driving the car, but there are limits.

            Now I'll let domesticated take the red pen to this post.

            YouTube Clicky!!

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              #7
              Originally posted by domesticated View Post
              I'm probably lowered somewhat close to 2". I have yet to find a camber kit that meets my criteria, so I'll deal with the extra camber on my track car.

              As far as the graph. Start at Y=0 on the graph. If you go 2" into jounce (lowered 2") the curve shows about 1" of camber change in the negative direction. You can also tell from this graph that the factory alignment isn't even perfect. Extrapolate for more low.
              Yeah it looks like its going into negative camber before it even hits zero. And the right is arching faster than the left.

              couple questions:
              Tire Grip . In a straight line I take it this is for take off, braking and travelling at high speeds. When you brake the front dips a lot on stock suspension, producing more camber on braking. So if lowered with camber and stiffer springs, would braking be affected a lot. as far as grip?

              Tire wear: Did you have a kit when it was daily-ed? and how was the tire wear if not.

              Comment


                #8
                Originally posted by sonikaccord View Post
                Honda made the car to handle very well for what it was supposed to do and during that period in time. It's not a performance car.

                When I first started learning to modeling the suspension, I used triangles as they are MUCH easier to work with but you have one of several points of the suspension geometry with arcs and pivots.

                According to my text, modifying the suspension geometry involves changing:
                Toe
                Camber
                Kingpin Inclination and offset
                Caster angle and mechanical trail
                Thrust line
                Ackermann steering geometry
                Roll Center and Roll axis
                Anti-Dive and Anti-squat

                "Messing up the geometry" is subjective as it depends on the person driving the car, but there are limits.

                Now I'll let domesticated take the red pen to this post.
                I'm going to take changing camber here as - adding a camberkit

                Comment


                  #9
                  Camber as in the angular change toward or away from the centerline of the car.

                  Adding a camber kit would change the upper A-arm length and alter the camber change characteristics as the wheel moves up and down.

                  Edit: A longer front upper A-arm on the CB7 would make the line on the graph more vertical as there would be less camber change as a function of "ride height."
                  Last edited by sonikaccord; 08-13-2015, 08:21 PM.

                  YouTube Clicky!!

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                    #10
                    Originally posted by sonikaccord View Post
                    Camber as in the angular change toward or away from the centerline of the car.

                    Adding a camber kit would change the upper A-arm length and alter the camber change characteristics as the wheel moves up and down.

                    Edit: A longer front upper A-arm on the CB7 would make the line on the graph more vertical as there would be less camber change as a function of "ride height."
                    The stock parts have a range of operation, including camber angles, and lowering pushes it closer to the edges of that range.

                    The other factors mentioned are adjustable with stock components, but not camber. So unless they're specifically talking about lowering, it must be adding a kit.

                    Im looking at it like driving around with really heavy tools in the trunk, or two really heavy people driving in the front all the time, compressing the front springs more. I don't think they changed the geometry, though adding camber.




                    The ball joint kit would change the length of the A arm, and it looks to me also the camber would change less with suspension travel.

                    Comment


                      #11
                      Originally posted by DCB7 View Post
                      The stock parts have a range of operation, including camber angles, and lowering pushes it closer to the edges of that range.

                      The other factors mentioned are adjustable with stock components, but not camber. So unless they're specifically talking about lowering, it must be adding a kit.

                      Im looking at it like driving around with really heavy tools in the trunk, or two really heavy people driving in the front all the time, compressing the front springs more. I don't think they changed the geometry, though adding camber.




                      The ball joint kit would change the length of the A arm, and it looks to me also the camber would change less with suspension travel.
                      That is exactly right. Lowering the car pushes you closer to the jounce limit. It has other effects. It's really not a 1 dimensional thing, that's why that jenga analogy fits so well.

                      I'm pretty sure they don't really know or care if those items are adjustable or not. They are saying anytime those values change, there is a change in geometry. There is a design goal in mind and camber is on that list. What the end user does that deviates from the design goal is what I believe most people mean when they say a change in "Geometry." Technically, it changes anytime and everytime the car moves.


                      If we use that definition, then weight added was calculated from factory and still in the design, but the geometry of the car does change when weight is added or shifted. If it didn't, vehicle dynamics would be nothing but constants(vehicle statics? ) and racing would be dry and boring. Luckily, physics doesn't work like that.

                      Camber is a change in geometry as it involves multiple pivots like you drew before. You can see how the imaginary triangles, with the pivot points as the vertices, change shape as you move and tilt the wheel in various directions. Anchor bolts move the balljoint pivot point out as well, therefore, it changes that triangle's shape and effectively lengthens the UCA.

                      YouTube Clicky!!

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                        #12
                        Originally posted by DCB7 View Post

                        In my understanding, they made the car to not handle well, therefore you have to drive it slower, thus it's safer. (It reaches the limit sooner though)
                        A car is never designed to not handle well. Other functional objectives will drive the design to have a lower limit, but a car is never purposefully designed to have a lower limit. Most cars are designed to understeer because it's safer. But you better believe the dynamics guys struggled to make the limit add high as possible.
                        '93 H22A 5SPD SE - MRT - DIY-Turbo Sizing

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                          #13
                          Originally posted by DCB7 View Post
                          couple questions:
                          Tire Grip . In a straight line I take it this is for take off, braking and travelling at high speeds. When you brake the front dips a lot on stock suspension, producing more camber on braking. So if lowered with camber and stiffer springs, would braking be affected a lot. as far as grip?

                          Tire wear: Did you have a kit when it was daily-ed? and how was the tire wear if not.
                          Straight line performance is reduced by camber. Too stiff of suspension can reduce compliance making the tire more peaky. Less weight transfer will improve braking performance assuming your brake torque distribution moves with it.

                          I did have a camber kit. But I ran -2.5 for years. Bad driving habits will wear the tires quicker than camber with good toe.
                          '93 H22A 5SPD SE - MRT - DIY-Turbo Sizing

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                            #14
                            Originally posted by sonikaccord View Post
                            That is exactly right. Lowering the car pushes you closer to the jounce limit. It has other effects. It's really not a 1 dimensional thing, that's why that jenga analogy fits so well.

                            I'm pretty sure they don't really know or care if those items are adjustable or not. They are saying anytime those values change, there is a change in geometry. There is a design goal in mind and camber is on that list. What the end user does that deviates from the design goal is what I believe most people mean when they say a change in "Geometry." Technically, it changes anytime and everytime the car moves.


                            If we use that definition, then weight added was calculated from factory and still in the design, but the geometry of the car does change when weight is added or shifted. If it didn't, vehicle dynamics would be nothing but constants(vehicle statics? ) and racing would be dry and boring. Luckily, physics doesn't work like that.

                            Camber is a change in geometry as it involves multiple pivots like you drew before. You can see how the imaginary triangles, with the pivot points as the vertices, change shape as you move and tilt the wheel in various directions. Anchor bolts move the balljoint pivot point out as well, therefore, it changes that triangle's shape and effectively lengthens the UCA.
                            Yeah, the imaginary line from point A to B is longer, but with the anchor bolts the physical arm is the same length as stock, but I see what you're saying.

                            Dynamics is the right word indeed (that's the very thing racing teams are competing at bettering, including driver dynamic), like when launching Im sure there is some 'give' in caster or 'thrust line' (?) or that energy would have to go elsewhere, and countless other variables. All those joints are meant to allow movement in a sphere of directions by design in different circumstances, including the car carrying a lot of weight with the soft stock springs. (ie, camber) They probably worked out the camber angle at full spring compression to give best grip to the stock tires.

                            It's clear the geometry involved is not as simple as ABC, and changes with as little as how much the driver ate for lunch, and his mood at the time, so it's not so absolute as just camber angle.

                            Originally posted by domesticated View Post
                            A car is never designed to not handle well. Other functional objectives will drive the design to have a lower limit, but a car is never purposefully designed to have a lower limit. Most cars are designed to understeer because it's safer. But you better believe the dynamics guys struggled to make the limit add high as possible.
                            Oh, I believe it. I meant in terms of performance, that may limit those other objectives, like comfort and user-friendliness. Like making a 90 degree turn at 15mph stock, it'll probably do the job, riding on the tire letters and all. Do the same turn at 20 and it might not turn at all. Or just understeer into the opposite lane. With a stiffer sway bar and wider tires the g-force would be too much for grandma, and the kids would be all over the back seat

                            I respect the engineering. I keep a bolt or two in my center console to remind me when I'm nonchalantly doing 70mph

                            Originally posted by domesticated View Post
                            Straight line performance is reduced by camber. Too stiff of suspension can reduce compliance making the tire more peaky. Less weight transfer will improve braking performance assuming your brake torque distribution moves with it.

                            I did have a camber kit. But I ran -2.5 for years. Bad driving habits will wear the tires quicker than camber with good toe.
                            Sure, if one is driving like Jason Bourne, 0 camber wont save the tires.

                            'reduce compliance' - meaning the weight transfer absorbed by the softer springs now go straight to the tires?
                            How do you reduce weight transfer? sway bar
                            Is it with 'brake torque distribution'- like with the prop valve? prop valve

                            Edit: did some reading
                            Last edited by DCB7; 08-14-2015, 08:39 AM.

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