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Recent content by BioMax

  1. BioMax

    Roll cneter on a track bar?

    "A wishbone is a slightly different animal, since its pivot point center is mechanically fixed to the diff housing." Agreed, but for simplistic's sake and assuming that you don't need to calculate the roll center to within ±.010, if you were to split a wishbone into a triangulated 4 link where...
  2. BioMax

    Roll cneter on a track bar?

    Drag cars are obviously not concerned about roll-center, but I have seen this type of lateral limiting device used on daily driven vehicles and have used them myself. Lets assume that all 4 4-link bars are parallel, from an overhead view, to remove any extra influence on roll center. Just a...
  3. BioMax

    Roll cneter on a track bar?

    I see it most commonly used on 1/4 mile cars. It would run from the lower rear mount of one bar to the lower front mount of the opposite bar.
  4. BioMax

    Roll cneter on a track bar?

    I tried to do a search for anything on this with no luck... How would you find the roll center on a suspension system using a track locator/track bar?
  5. BioMax

    Air Spring

    It can get a whole lot more complicated than that. The steel spring, at rest, has no stored energy, but the air spring, needing a certain volume of air to be a spring, will be constantly fighting the suspension to "get out," much like torsion bars. On lighter vehicles that will be seeing some...
  6. BioMax

    Air Spring

    I work with air springs everyday, they do absorb a small amount of energy, but their aggressively rising rate and the amateur’s habit of installing too small of a part make the statement negligible. But, with the right size part and some time spent playing with expansion tanks of different...
  7. BioMax

    Long travel suspension geometery

    I recently had a similar question. A friend of mine told me that he concerns himself with side-scrub first, then camber and roll-canter. I concern myself with camber, then roll-center and no concern of side-scrub at all. I set up the lower a-arms to point down about 2” from the center out, so I...
  8. BioMax

    Off-road roll-centers

    This is sorta a 2 part question, okay mabey more... ...On a typical trophy truck, or really any other off-road 4-linked vehicle, the upper triangulated bars are, typically, "run" wide on the chassis and come to either a single point (ie. wishbone style 3-link) or close to each other on the rear...
  9. BioMax

    Polar moments of inertia...

    Okay, that does make a little more sense. Thank you! Fabrico: On a different site... there is a guy saying that there is someone out there who is running a genuine reverse 4-link on an a truck, that even finished the 1000. Have you seen the truck or even heard of it?
  10. BioMax

    Choosing camber curves

    "BioMax, your car sounds interesting and similair (although mine will be ~1800 lbs). I have used those same rough numbers for suspension travel and ride height. I have not yet decided on anti's just yet. How is the steering feel with only 5 degrees of castor? Do you run P/S?" Brian- I am by...
  11. BioMax

    Polar moments of inertia...

    I'm not going to tell any of the TT or class 1 guys that they're over kill. I know with the new trend heading towards 39" tires, the weight that is carried around (sprung and unsprung) is tremendous. Especially with the horsepower that the engine builders are capable of, there is that much more...
  12. BioMax

    Polar moments of inertia...

    I cannot deny that from the outside looking in not many of the trucks look like they should work and yet they work exceptionally well. I just look at some ot the rear suspension systems "they" are using. Those with what I believe to be called, mesanine arms. On top of that 4"x.250 wall axle...
  13. BioMax

    Polar moments of inertia...

    I can agree with it being much more fun in the dirt than on the street... What about over bumps? If the vehicle is upset vertically the suspension would be forced to absorb the movement and then the unsprung weight would be folowing the bump (as best it can) rather than being used as polar...
  14. BioMax

    Polar moments of inertia...

    This is more of a "fire starter" I think, but I would really like to get some outside oppinions. On any on-road car you would want low polar moments of inertia, for fairly obvious reasons. BUT on off-road desert vehicles "they" are leaning to high PMI. The theory is solid, in that low PMI allow...
  15. BioMax

    Choosing camber curves

    I built a full tube chassis Chevelle with a-arms on all four corners. The camber gain I ran was 1 degree for every inch of travel and a lower front roll center than the rear. Total travel on all four is 8" and ride height is right at half travel. I ran a small amount of anti-dive and a very...

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