Thread: New Veyron Test
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Old 12-30-2006, 06:09 PM   #63
tforth
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And what is with all the weight vs. handling crap. Weight, or mass, has no direct relationship with the centripetal acceleration (i.e. 'g') experienced by a vehicle during a cornering manoeuver. Center of gravity, track, roll stiffness, roll center position, coefficient of friction of the contact patch on the given surface, transient contact patch stability, etc. would play into this metric. I suppose that next your going to claim that weight is what limits its top speed as well...

Thats where your wrong. Weight, or rather mass has a significant effect on handling. cg roll stiffness roll couple influence the contact patch.. But.. F=ma.. Thus the force required to accellerate a car laterally (realizing that the new force vector is a combination of lateral and vertical forces) is higher for a higher mass car. Thus requiring more friction force on the tires, and hence more grip. Now the items you mentioned influence more grip based on the amount of tire that stays connected to the road during turns (invarious situations), but there is a point where it just won't be enough. Cars arent just light for acceleration purposes. Actually, I've just oversimplified.. Why? Because mass also influences the friction force. The coefficient of friction is a function of the force pushing down, gravity. Thus at least theoretically (we wont get into things like tire deformation), heavier mass increases the friction at the tires. Hence a heavier car would theoretically have a higher tire grip, but it requires a stronger force to hold it to the turn.

If your arguement worked we could go auto xing with a semi if we lowered the ride height and installed better suspension.
You're right in the sense that mass is directly related to the accel. rate. The point I was trying to get across is that mass in isolation does determine the accel rate. There are many other factors that play into this.

Specifically, I was irritated by the general statement that because the Veyron weighs 'x', it cannot do 'y'. That's like saying: because a car has a 4 cylinder engine, it cannot travel faster than 'y' mph. These are oversimplification statements. The Veyron appears to be somewhat of an exception in this regard, as several reviewers have stated that it feels approx 300-400 kg (660-880 lbs) lighter than it is. However, I am not aware of anyone credible saying that it feels as light as an Elise...
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