Why slimming world is a waste of time

Posts about anything do to with modifying your car such as fitting aftermarket parts, bodykit, or tuning the engine for more performance.

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lower
Posts: 438
Joined: Tue Dec 14, 2004 2:05 pm
Location: Leicester

Re: Why slimming world is a waste of time

Post by lower »

you're wrong about that. force does not equal weight.

when the car is driving along and generating downforce there is indeed additional load on the tyres but only downwards. when the car comes to a corner this force is still only transmitted downwards to assist with grip. if you were driving a car that applied the same amount of pressure downwards when driving in a straight line because it weighed more, you would have considerabley more momentum to change direction when you came to a corner and its cornering abilities would be way below that of a car that generated the downwards pressure through its tyres using downforce.


in the 5th gear feature, the reason that the f1 car suddenly lept ahead of the bike was that the bike had so much less power. initally, off the line, the lighter bike was able to accelerate at a similar rate to the f1 car. as the speeds went up, drag caused by wind resistance starts to play more of a part in acceleration rates than mass and thats when the significantly more powerful f1 engine let the f1 car continue accelerating much faster than the bike.



No, you didn't!

Downforce is downforce, mate - exactly that, ie FORCE, ie WEIGHT!

And we're not even taking into account the extra drag from converting air speed into downforce.

Bottom line is, those wide tyres don't work unless they've got some severe weight on them.

Did you see a feature that "5th gear" did a little while back, running Jenson's BAR against a racing bike against a powerboat? The F1 car was pretty level with the bike up until about 70-100mph, and then all of a sudden, once the downforce started coming into play, it left the bike for DEAD!

4G cornering, anyone?? ;)
PsychomIKE
Posts: 130
Joined: Fri Jan 21, 2005 12:01 pm

Re: Why slimming world is a waste of time

Post by PsychomIKE »

Ah, clear head today :)

Lower has summed up what i was trying to get at, but failed miserably to explain.

Weight and Mass are too entirely different things.

Mike
MR2Mania
Posts: 2149
Joined: Wed Dec 15, 2004 10:37 pm
Location: UK
Contact:

Re: Why slimming world is a waste of time

Post by MR2Mania »

PsychomIKE wrote:Ah, clear head today :)


Yes, me too :-)

I have to admit that I wasn't thinking straight. After all, it's to do with mass. After all, F=ma. Since aerodynamic downforce doesn't change that mass, the centrifugal force (the force that the tyres must be able to hold laterally if the car is not to slide) created whilst cornering still depends on the mass of the car. So to hit the same cornering G (ie -a in that equation), the lower the mass, the lower the force put on the car sideways.

So, yes, you're right, the aero doesn't affect this, and the ideal is to have as low a mass as possible with as much downforce as possible.

Here's a good article:
http://www.insideracingtechnology.com/tech106force.htm

Right, time to make a run for it... ;)
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