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  1. Komodo86

    Brake Cooling for Car

    Bigger discs, both in mass and surface area.
  2. Komodo86

    Mileage versus travelling Speed ?? Is there truely exists something like fuel economy Speed?

    Ah, but to offset this, a large engine typically runs much longer gearing, allowing the engine to turn slower giving lower friction losses and requiring more throttle to be used. Low RPM, wider throttle position usually means that they can return reasonable economy vs a much smaller engine with...
  3. Komodo86

    Braking at high speed vs low speed.

    Well, quite. There is a lot of variables! I am not convinced that it easier to lock up the wheels at lower speeds. But some people are. To my mind, all else being equal, there is the same normal force on the tyres in either case, so the same brake force can be applied. What is not constant (and...
  4. Komodo86

    piston speed

    A 100mm stroke at 7500rpm has an MPS of 25m/s. The peak piston speed with a 150mm rod is 41.22m/s. With a 200mm rod is 40.42m/s. A change of about 1.9%. Is that significant?
  5. Komodo86

    Mileage versus travelling Speed ?? Is there truely exists something like fuel economy Speed?

    Speed requires power to overcome drag. An engine consumes fuel according to it's BSCF and the power generated. BSFC is lower at higher loads, so effectively as the speeds increase, the BSFC decreases. Obviously, there is a sweet spot, and either side will see an increase in consumption, but...
  6. Komodo86

    Braking at high speed vs low speed.

    I am interested in the forces at play determining wheel lock up at different speeds. Lets say a car is capable of locking the front wheels up at 130mph. Does it lock up the wheels significantly easier at 30mph? If so, why? If we assume it can generate the same acceleration level from both...
  7. Komodo86

    piston speed

    What I should have said above is, has that theory/observation been done at piston speeds significantly over the speeds mention here?
  8. Komodo86

    piston speed

    That might be a trend over the majority of the RPM range, and it makes sense. Is it definitely the case as the piston is approaching/passing around 27m/s though? Have there been any studies to specifically study this aspect?
  9. Komodo86

    no droop suspension

    Another effect of ZD setups that I have observed on my self built 3D kinematics models (and I do appreciate I might not have the load transfer theory 100% correct here) is that when the inside wheel tops out, the outside wheel continues compressing at it's normal rate. The effect is that the car...
  10. Komodo86

    piston speed

    Another plausible reason is flame front speed. I've seen speeds of 100ft/sec mooted. That's 30m/s. So a combination of inlet mach index and 'outrunning the flame' is the most likely answer. If the mach index doesn't get you, the flame speed will.
  11. Komodo86

    piston speed

    I'm not so sure it's to do with materials, and more to do with the mach index in the inlet ports nowadays. The theory is that engines effectively choke above 25-26m/s, without a LOT of work. A drag engine, as I assume a 14000rpm SB Ford to be, are not really comparable to anything designed to...
  12. Komodo86

    Air flow and fuel flow calculations

    OP this one does fuel flow rate amongst other things: http://blackartdynamics.com/Engine/EngineThermodynamics.php I don't know if it is any more useful to you really as the inputs may be limited for what you want, but might be worth a look.
  13. Komodo86

    piston speed

    Accepted maximums are closer to 5000fpm (25m/s) nowadays. You won't find many, if any, production cars exceeding that level. You'll not find many racing engines designed with any degree of endurance surpassing it either. Drag engines are another matter.
  14. Komodo86

    Racing car without swaybars?

    Ok, I had the wrong terminology there then, thanks!
  15. Komodo86

    Racing car without swaybars?

    FLLTD = Front Lateral Load Transfer Distribution i.e. how much load transfer has happened at the front. It changes with lateral acceleration. Perhaps it should be called 'Front Diagonal'. Whatever it is called, the differential between front and rear load transfer is not constant.
  16. Komodo86

    Racing car without swaybars?

    Er, god knows then! Tilt test would be best for you, shouldn't be too much hassle looking at the work gone in to the build!
  17. Komodo86

    Racing car without swaybars?

    It might not be a lot in absolute terms, but in relation to the sheet sheets of ally and perspex windows it shares it's space with up there, it will be heavy. It won't affect the CG greatly, but it will certainly raise it slightly vs having no cage at all. Given the spartan interior and I'm...
  18. Komodo86

    Racing car without swaybars?

    Just to expand on this some more. At 0g, '0% LT', FLLTD is 50%. At point of both wheels become unloaded, FLLTD is also 50%. Lets call this '100% LT'. Let's look at 10%, 20% and 30% LT. 2000lb 50/50 SWD, with a 60% front RSD. At 10% LT there is 200lbs LT, of which 60% is taken by the front...
  19. Komodo86

    Racing car without swaybars?

    Rollcage is heavy and high mounted though... ;) Really, the only way to be sure is to determine it with a tilt test, but it's a bit time consuming as you need to replace the front suspension with rigid links to do it accurately.
  20. Komodo86

    Racing car without swaybars?

    Yes, RX8 is also in the 18" region, Porsche Cayman and Toyota GT86 are also very low in the 17-18" range. These are all very low CG production vehicles. Work from those examples and have a think about where the weight is in your car. A saloon car with a high roofline, large glasshouse, upright...

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