Bruce Nice thoughts....
I only run Ballast at Bonneville because I had such good luck with it at
Muroc... little ballast in the back of the car and it was 10mph faster...
simply because I could hook it up in the middle gears... and on the big end
with the Nitrous on... ( I also added 6 degrees of Spoiler )
Think of Maxton as a long drag race.... Just like you would think of Muroc
or El Mirage I am sure... you only need the ballast that is nessesary to
gain the traction required to accelerate to as close to terminal velocity as
possible....
Where you have limited time to accelerate to your top speed ... Weight is
an issue as you have to overcome that mass to accelerate in a given
distance....
As Dave said.... Keep in mind that the added weight has to be compensated
for in Rolling resistence.... and you have to stop that mass.... so it's
harder on everything concerned....
Lets go back to the original reason we run Ballast anyway.... seems as
though you can get Traction through Downforce... and Downforce can be added
by either of Two Methods... Ballast or added Spoiler if your class allows
one.... ( or you can adjust the attitude of the car with an Air Ride )
the Fact that we have so much Distance at Bville to accelerate allows us to
use Ballast rather then add the spoiler.... The Spoiler adds Aerodynamic
Drag as a result of the negative lift it is creating.... and it takes HP to
overcome that drag... It also take HP to overcome Rolling resistence... but
the theory is that it takes less then the Drag created by the spoiler....
Keith ( gotta quit I am totally lost )
---- Original Message -----
From: <FastmetalBDF@aol.com>
To: <lsr_man@yahoo.com>; <kturk@ala.net>; <landspeedracer@email.msn.com>;
<land-speed@autox.team.net>
Sent: Tuesday, January 02, 2001 5:45 PM
Subject: Re: Maxton Ballast
> Hi Dick ! Just my own opinion ( and everybody has one ) :
> Railroad rail is great for making up little mini anvils for in your shop
or
> out
> in the driveway ........ and also for running trains on . NOT GOOD at
all
> for ballast ...... you need long, clumsy lengths to get any weight at all
> ......
> it is not COMPACT enough . THICK steel plate takes up much less space
> and can be stacked and fit down LOW where you want your ballast
> positioned ..... BUT ..... LEAD is much better ...... you can melt it and
fit
>
> it into custom made containers that are duck soup to weld up and mount
> exactly where you can fit them in, and as Dale mentioned, lead shot can
> be an "adjustable "source of ballast ....... if you want to be scooping it
in
> and out, or handling little bags of it . Water is only 62.4 pounds per
cubic
> foot, or 8.33 pounds per gallon, so it is third rate when compared to
> steel or lead in any given cubic measurement . The advantage water has
> as ballast is it can be added or removed easily near the racetrack, so you
> don' t have to tow that dead weight . We ran some water ballast at
> Speedweek, but would have been much better off with more lead for a
> greater total weight of ballast . Railroad track is easy to mount as you
> can just torch some mounting bolt holes in the web ...... quick n' dirty
> ......
> but it certainly LOOKS like a " jury rig / baling wire " approach to
building
> a nicely crafted race car of any type . I also feel the majority of your
> ballast
> should be concentrated WITHIN the wheel base of car to give the car a
> lower polar moment of inertia, ie; not heavy out at the ends ..... and as
> LOW as is feasible to help maintain a low center of gravity ...... this is
not
> drag racing, where guys used to mount ballast ( and engine / trannies )
> way up high to get additional weight transfer to the rear slicks when they
> launched . That is why NHRA put the 24 " MAXIMUM crank centerline,
> at front pulley, to ground rule into effect ...... or somebody would have
> built a car with the carbs at eye level to get a little more bite . We
knew
> of one VERY WELL KNOWN engine builder / match racer / and pro stock
> builder / driver / HERO who had lead ( lots ) poured into the extreme
> rear / upper insides of his rear fenders, just leaving enough room to
> squeeze the tail light assemblies in place . Another successful
> application of " EVERY LITTLE BIT HELPS ! "...... IT WORKED, even
> if quite ILLEGAL !
> Since a pound of feathers weighs JUST AS MUCH as a pound of lead,
> I guess just about anything could be incorporated into the car as ballast
> ...... but I also think a race car should reflect sound ideas, a high
degree
> of workmanship, and some time spent in what the overall requirements
> are, the compromises that have to be made to attain maximum performance
> with the parts and funds available, and some good old back yard
> engineering that has enabled HOT RODDERS to achieve the speeds and
> records they have for quite a few DECADES now !
> Have FUN building your wheels ...... and if you already have the
> RR track ..... you might want to weld a piece of 1 / 2 " plate on one
end,
> stick the other end in some concrete outside your garage .......
> and have a very handy welding / grinding table for those fair weather
> days you have down there in Texas . This can help keep your
> shop clean when doing lots of fabrication .......
> Bruce, on frigid East coast,
> recalling those hot days in Utah, last year .......
>
> Rome wasn' t built in a day .......
> and neither are nice racecars
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