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  1. JohnLear

    Whiteline ALK

    PP, I may have got it wrong, but I read it asking for comment / confirmation of a statement, not as a rhetorical question, i.e. I interpeted it like this; "Extra front Caster is usually a good thing. Right?".
  2. JohnLear

    Whiteline ALK

    TravWood wrote:"Extra front Caster is usually a good thing right?" Please preface all comments with 'IMO': It depends on the details of 'extra' and 'usually', and for what purpose the car is being used by what drivers. If trying to improve the handling capabilities of a production car...
  3. JohnLear

    Two Strokes Strike Back

    That's not my understanding. Piston port engines have the intake port in the cylinder barrel, reed and rotary valve engines have the port on the crankcase, well below the cylinder...
  4. JohnLear

    Whiteline ALK

    If I'm understanding this correctly, lowering the rear end of the 'wishbone' will alter the angle of it's pivot axis (up toward the front / down toward the rear, to state the obvious). With a Mac' Strut this will (to some degree) lessen caster increase with bump motion and lessen caster decrease...
  5. JohnLear

    Axle Wrap point of rotation

    I was thinking the same thing as Norm. I can't see the axle shaft axis as being definitive, surely the centre of rotation must be a product of the spring geometry and the distribution of stiffness within the spring?
  6. JohnLear

    Creating steering that feels alive

    Greg, I'm sure there's a lot in what you're saying, and I understand that the game physics model must needs be a rather crude over-simplification of the almost infinite complexity of reality. The lack of any meaningful feel (with a simulator steering wheel, not a pad like the kids use...
  7. JohnLear

    Creating steering that feels alive

    Norm, My experience with racing car games is that the 'driver' and the 'car' exist in slightly but disconcertingly different time zones. When the 'driver' makes an input there is a significant time delay before that input is seen on the scree All those electronic calculations don't occur...
  8. JohnLear

    Relationship between axle torque and wheel torque

    So assuming equal torsional stiffness per unit of shaft length, the longer drive shaft (including everything from the hub to the differential) will twist slightly more than the shorter shaft (this additional motion taking a fraction of a second to occur...). Won't the differential planetary...
  9. JohnLear

    Welding to A-arms?

    I have welded onto stressed forged components a number of times with no problems, and if it were my project I'd be happy to do it. I very much doubt there is any heat treatment (i.e. hardening / tempering) of the control arm forgings, but I could be wrong. It might not be a bad idea to heat...
  10. JohnLear

    Relationship between axle torque and wheel torque

    Sorry, should read: "So, with a modern well engineered FWD drive train, torque steer (that isn't caused by an outside factor such as road camber, unequal alignment or tyre problem) should be non existant...?
  11. JohnLear

    Relationship between axle torque and wheel torque

    "But "Torque Steer" is a good illustration - this is where the axle is longer on one side than the other and some of the torque is used to twist the longer shaft." I've heard this for years, but could never understand why any diference in axle 'wind up' wouldn't be accounted for in the...
  12. JohnLear

    Anti-roll bar material

    If changing the dimensions of the ARB is not an option, and you simply must have less roll stiffness at that end of the car, then possibly the only (?) option might be using softer springs?
  13. JohnLear

    Anti-roll bar material

    My understanding is that the steel from which the ARB is made (both material grade and treatment) is more or less irrelevent as far as torsional stiffness is concerned. The material should of course be a 'spring steel' appropriately heat treated, but this is a longevity issue rather than a...
  14. JohnLear

    highest reving automobile engine

    "I seem to remember a BRM H32. I think it never made it to a race." There was a 3litre H16, effectively two flat 8s stacked on top of each other. I can't recall if it ever raced. The BRM 1.5litre V16 makes an utterly astonishing sound, there are some recordings of it floating around on the...
  15. JohnLear

    How To - Transmission Re-Design

    Umm, gearbox oil, I'm no gearbox wizz, but I would expect that so long as one set of gears (on a shaft) is sitting in the oil bath, then plenty of oil will get flung around. I'd be checking for baffles (internal reinforcing webs) that might block oil from running into the 'bottom' of where the...
  16. JohnLear

    How To - Transmission Re-Design

    Depending on output shaft height relative to input shaft height, it might result in the inner CV joints being relatively high, thus possibly downward angled driveshafts, and probably a somewhat higher gearbox mass (free lunch anyone?). The reason I suggested it is that I vaguely recall that...
  17. JohnLear

    How To - Transmission Re-Design

    Probably a stupid suggestion, otherwise I suspect it would have been suggested already, but is there any chance of running the gearbox upside down?
  18. JohnLear

    exhuast ...suction charging...

    Might not placing the exhaust outlet in an area of low pressure (e.g. behind the seat / rider on a racing bike) help to 'fill' that area of low pressure, and thus (slightly) decrease drag? I've always assumed this was why so many racing bikes have such high and centrally located exhaust...
  19. JohnLear

    Differences between Automotive Engineering and Motorsports Engineering

    Priorities that may affect handling etc might have nothing to do with the suspension per se. These days nearly all sedans seem to feature fold down rear seat backs that expose a large aperture between the cabin and boot (trunk) cavities, to allow long cargo to be carried. In the old days this...
  20. JohnLear

    Puting a 4 link on a unibody???

    Spool on a road car is a PITA, I had one temporarily in a Lotus 6/7 type sports car (i.e. a 'Nota Sportsman'). Not reccommended at all mostly because it will actively try to kill you on a wet road (even at walking pace...). The one redeeming feature is that if you snap a half shaft you can...
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