WHOA..... Guys we are losing something here in the translation....
We first need to define the difference between instant center....( point in
the car where mechanical forces are applied ) and Aerodynamic Center of
Pressure.... They are not the same thing....
A short wheel Base car is NOT more stable then a Long wheelbase car....
little logic goes a long way here.... the longer the car the longer the
arm can be where force is applied.... Longer lever.... better leverage...
hmmm
are the front wheels getting lighter because of the Traction associated
with the rear tires.... hmmm sure I think that is why we see wheel stands
at a drag strip.... at Bonneville we don't have that kind of traction...
Keep in mind at Speed we have aerodynamic pressures on the nose of the car
as a matter of impact air... and that downforce in conjunction with the
other aerodynamic aids we have ( spoilers ... air dam's so on ) converts
into what the Total aerodynamic pressures are on the car.... the sum of all
of these forces equals some amount of Force.... where that force is
excerted called the center of Pressure.... the NET effect of Both of these
is the total downforce on the car.....
Now if we can develop the Traction of a Top Fuel car.... then I think the
Blow over is an event we need to think about when designing a car.... in
the mean time on Stock bodies the critical dimensions are going to be
length and Frontal area.... Longer is Good... and the smallest frontal area
is Very critical.... which is more important to you is a matter of
choice.... ( yeah I bet there is a logical solution to this on paper
somewhere... I ain't smart enough to sort it out.. I just know what has
worked in my case )
Keith ( okay Dan Help Mr. wizard... I am totally lost)
I can't in my mind anyway figure out how a short car would handle better
then a long car out of all that..... Keep in mind car's like Jack's Truly
are like a lawn dart.... the longer they are the straighter they go....
with less impute.
----------
> From: George Mitchell <americanpartnerinrussia@starpower.net>
> To: FastmetalBDF@aol.com; Dale.Clay@mdhelicopters.com;
landspeedracer@email.msn.com; Flowbench@aol.com; lsr_man@yahoo.com;
fosterap@flash.net
> Cc: kturk@ala.net; land-speed@autox.team.net
> Subject: RE: Ballast & Handling
> Date: Wednesday, January 03, 2001 9:11 AM
>
> snip<Those long wheelbase cars
> reduce the weight on the front tire patch>
>
> so why would you want less weight on the front tire patch if that is
whats
> going to steer you out of trouble ?
> If the leverege can make trouble down course worse then why wouldnt a
> slippery small car work better than a slippery longer one . Note-- I am
> talking Monza vs Firebird -- not roadster vs streamliner--or are they
pretty
> darn close?
> Im just thinking wheelbase here. I know that the Firebird that we ran
> handled better than the Monza but now you all have me wondering why. I
> thought it was all about the wheelbase.
>
> would the center of pressure on a production car be somewhere in the hood
or
> somewhere in the winshield? Meaning is it where there is the most
pressure?
>
> Aren't you guys happy I'm working out of my house now? Lurker days are
over
> !!
>
> George in DC
>
>
>
> -----Original Message-----
> From: owner-land-speed@autox.team.net
> [mailto:owner-land-speed@autox.team.net]On Behalf Of
> FastmetalBDF@aol.com
> Sent: Wednesday, January 03, 2001 2:05 PM
> To: Dale.Clay@mdhelicopters.com; landspeedracer@email.msn.com;
> Flowbench@aol.com; lsr_man@yahoo.com; fosterap@flash.net
> Cc: kturk@ala.net; land-speed@autox.team.net
> Subject: Re: Ballast & Handling
>
>
> And EVERYTHING that DOES NOT move HAS to obey the laws
> of physics, likewise . If the car encounters yaw, the lengthened
wheelbase
> multiplies the effect of the air pressure acting upon the leading side of
> the
> nose, increasing the chance of the car getting sideways, the same way as
> if you held a ping pong paddle out the window of a car at speed ......
> you might be able to hold it somewhat steady at this speed, but not if
> it was fastened out on the end of a broom handle, or such .
> It is all leverage. As you stated the longer wheelbase does give the
> driver a much better chance of making the corrections sooner to
> keep it on the straight and narrow . Those long wheelbase cars
> reduce the weight on the front tire patch, so all this has to be a
> consideration ..... and we' re not even getting into aerodynamics here !
> ...... fascinating subject ...... or is that FASTinating ?
> bdf
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