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IanF

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    senator 3.0 24v

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  1. The Bose system seems to be a fully active system. Not sure I'd want to trust the long term reliability of such a system when compared against say a simple spring and orifice damper. The MR system is intriguing. Some dampers contain a motor that controls the size of the orifice within the damper. But this approach doesn't offer real time control of the dampers characteristics. On the MR damper it seems that they have used a fluid whose viscosity can be controled by an applied magnetic field. I haven't got the feintest idea just how usefull such real time control would be for road use, though at least it should fail safe when the electrics plays up.
  2. I wonder what would happen if you(roger or Tony that is) were to phone them up and ask what they do for the money... They may be happy to explain what kinematic toe is and how it works/matters/ cost £150
  3. IanF

    Corner weighting

    I don't understand the question. So can't possibly answer
  4. this lot www.performancetrends.com have a piece of software that allows the simulation and visualization of suspension systems. There software has time limited demo modes.
  5. http://users.bigpond.net.au/lachlan/tech/rosejoint.html okay so its a modification to the control arms but I guess its similar in principle.
  6. is the wear pattern repeated at equal intervals all the way around the circumference?
  7. I'm no expert but I know that ALL GREEN does not mean ALL GOOD. Symmetry between left and right is probably more important than having everything green. It doesn't seem like a good idea to have both rear wheels pointing to the right. When Tony gets here I hope he will explain what 'Steer Ahead' means. Also if you do go elsewhere ask for a full geometry check and a full printout. There is really no excuse for just giving you the bare minimum of camber and toe measurements. ======================= Regarding price of the rear track control arm; are you a member of any car clubs?
  8. Curious... has the inner rod actually broken or has it 'just' fallen out of a socket in the top cover? have to cut open the top cover to see how the inner rod is connected to the top bit (LOL there's a song in there somewhere #The damper rods connected to the knuckle joint....#) The damper supresses the inherent resonance in the spring mass system. So as long as you avoid driving at just the right speed over a bumpy road the wheels ought to stay in contact with the road. Could be fun, in an old banger that is. Theoretically even small bumps will get a damperless car airborn if you get the speed and bump pitch just right, I say theoretically because I have no personal experience but some mad fool must have tried it.
  9. When the springs are removed do they return to their correct shape? If they do then as far as the spring is concerned the collapse is the correct behaviour. Maybe not what the customer wants but the spring doesn't care about that
  10. Would you agree with the placement of 'F' X+F Y+F Z+F as a resultant dynamic position.... and indeed moment so say the Governor I'll give a couple of responses. Mostly because I'm not quite sure where you are comming from with the desire to say X+F 1) I don't think any of my profs would have been happy about my playing fast and loose with the seperate ideas of position and force. When you try to solve problems in statics involving position and deflection you work exclusively with the forces. The positional information is incorporated into the force diagrams because force has magnitude, direction and a point of action. This point of action is the whole XYZ thing. These force diagrams always form a closed path as there can be no 'resultant' in a static system. Even though the overall aim of such diagrams is a zero the sizes and directions of the forces are instructive. Used to predict deflection and component failure. 2) Hooke's law.There is a well known relationship between Force and extension (position). Indeed since there are no physical materials that are infinately stiff. Hooke's law always applies, its just that often many of the deflections of the components that form a cars steering system can be ignored. Some of these ignored deflections have important implications such as the choice of toe-in over toe-out. But I dont have the experience or expertise to understand how these ignored deflections influence the behaviour of a car. They usually show up in the dynamics (where time T is involved). Shimmy is the only one that springs to mind. If I ponder a bit more I may think of a third response to the 'X+F' Force is important I can see why you want to include it as the unspoken fourth dimension. But I'm not sure where you are taking me. I hope the ride wont be too harsh (more dynamics *grin* )
  11. There are three HSVs and two VXRs in the car club I belong too. I don't know if its possible to get comparative data from them. Most if not all the comments on the quality of Vauxhall main dealer competence would be unprintable.
  12. Waves his engineering degree. Maths rulz down wiv spellin. X, Y, and Z and you are firmly in the realm of statics. Add in change ie time and you are into the much harder subject of dynamics. The math for dynamics gets hairy very fast. To make it worse real systems are non-linear. Very awkward stuff where one plus one does not make two At this point you end up reaching for a big super computer. Even then you have to build the damn thing cos the real world just doesn't seem to want to agree with the output of the computer models. Thats where experience and expertise comes in. So no I wouldn't have picked F but then the whole topic of dynamics is enough to bring me and my computer out in a sweat!
  13. slip ratio = (speed of roadwheel/ vehicle speed) -1. +ve slip = accelerating. -ve slip = decelerating. I found a reference that indicates that ABS systems work by calculating the rate of change of wheel speed. If this is the case, then ABS wont operate under the rolling turn in the first post, as this is a steady state condition. Using rate of change of wheel speed would make my earlier statement that ABS has a target slip as part of its control strategy incorrect. There is an optimum slip for both braking and accelerating but the ABS doesn't have to care about optimum slip to function. The same isn't true for TCS though. The book indicates that Traction Control is more complex than ABS and that the control system has to adapt its target slip values to different road conditions and to allow for the negative effect that slip has on cornering. (negative unless your aim is drifting that is). One of the strategies used by the TCS designers to cope with different raod conditions is a driver selectable off switch LOL. [bTW How do I post pictures? I could then post the graph showing how friction varies with slip from the book] reference : An introduction to modern vehicle design editor Julian Happian-smith. chapter 11: control systems in automobiles. graphs taken from Chowanietx and Jurgen 1995)
  14. these figures are from a couple of years ago... All numbers a before left before right then === the after figures for left and right F CAMBER -1o 02' -1o 08' ==== -0o 58' -1o18' F CASTER 4o 19' 4o 50' ==== 4o 19' 4o 50' F TOE 5.0mm -8.4mm ==== 1.0mm 0.7mm F SET BACK left 0o 13' ==== left: 0o 15' INC ANGLE 13o 25' 13o 52' ==== 13o 29' 13o 42' SAI 14o 27' 15o 00' ==== 14o 27' 15o 00' R CAMBER -1o 37' -1o 46' ==== -1o 34' -1o 46' R TOE 2.0mm 0.4mm ==== 1.5mm 1.0mm R SET BACK right 0o 07' ==== right 0o 03' THRUST LINE right 0o 07' ==== right 0o 03' I don't know what the correct figures for caster SAI KPI should be. The printout did indicate that the Caster angle was out of spec both before and after adjustment. I am suspicious of the CAMBER figures as they did not check either the fuel level in the tank or use any weights in the car. Something that I was later told should have been done. I have to locate another geometry shop and get the car remeasured. So here I am engaged ina crash course on geometry LOL. A little knowledge may be dangerous but no knowledge is far worse. The car is a 24V 3.0 Senator 1994.
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