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Re: TC thought

To: Dave Dahlgren <ddahlgren@snet.net>
Subject: Re: TC thought
From: Joe Amo <jkamo@rapidnet.com>
Date: Sun, 02 Dec 2001 12:10:32 -0700
Some of us  (me included) just enjoy doing things the "wrong" way

Dont forget, FIA and FIM, anything goes and is open
to everyone

Joe :)

Dave Dahlgren wrote:

> Well actually an active suspension is a great idea. I would assume you would 
>want
> it to get stiffer with speed..The real problem is with unsparing weight 
>though.
> And some of it is hard to loose in this type of racing but some can be lost.
> Brakes are the first place i would look as if you can only acell at .61 g 
>then i
> suspect any set of brakes that can decell at a greater rate are over kill. 
>Inboard
> suspension would help too but it is fairly complicated and spendy. That gets 
>us
> down t the wheels and tires. The tire weight is pretty well fixed by the
> manufacturer and the rest is open to a weight reduction. Carbon fiber wheels
> perhaps? thin wall titanium maybe? I think in the end you would have to use 
>all
> these tricks and still have to have a suspension that has almost no give at 
>300 +
> but it would certainly make getting to that speed easier. that is the whole 
>point
> in my mind. When you race a LSR car where terminal velocity is the real goal 
>then
> you have to see what you can do to make the track seem longer. I think along 
>the
> lines of getting to the greatest speed as soon as possible on the course so 
>that
> there is more course left to get the last mph out of the car. The way to do 
>that
> is to accelerate as fast as possible as soon as possible. The ways I see to do
> this are as follows
>
> 1. As light a car as possible
>
> 2. gear spacing and as many gears as it takes to stay in the power band and 
>not
> shock the tires during a gear change.. I am writing some software to address 
>this
> problem so it can be visualized very quickly and sensible choices made.
>
> 3. Traction / wheel spin control via power modulation to cover up the holes in
> traction left by available gear spacing combinations
>
> 3. Suspension active or other wise that will help the car hook up initially 
>and
> then have appropriate response times to suit the speed desired. ( this is the 
>most
> complex problem).
>
> So my view of racing LSR has broken every rule known to be true..as i have 
>heard
> them anyway.
> 1. ballast is good make the car heavy
> 2. Gearing is unimportant just give it a push and let it go you have 5 miles..
> 3. Traction control is both illegal and frowned upon in general as it takes
> control away form the driver.
> 4. Suspension is pretty much not needed and causes more problems than it 
>fixes.
>
>  My answers to these myths are
> 1. there is no such thing as a good heavy race car. if you need ballast fix 
>the
> car.
> 2. gearing is everything. I can gain more speed by shutting the hood and 
>working
> on the rest of the car provided the engine is a 'player' to begin with. If you
> tweak the engine endlessly the best you can hope for is a few percent from 
>test to
> test on a well developed engine. With proper gearing I can get all that power 
>to
> the ground and stay in the power band I spent so much time and money 
>developing.
>
> 3. TC well if you ask a driver what he/she did in the car and how the run was 
>you
> get one story. Ask someone that watched the car you get another story. I use 
>the
> word 'story' intentionally as most of these recollections are just that, a 
>story
> but not necessarily the truth. Down load the data from onboard sensors and you
> will get the truth. I have seen more passes at part throttle in cars where the
> driver said the car was going well and hooked up than you might believe. So 
>in the
> end the driver seldom has a real clue a to what went on other than the big 
>'Kodak
> moments' when a wheel fell off..
> 4. Suspension is the final link between the mass you are trying to accelerate 
>and
> the tires that have to get the power on the ground....
>
> The real issues with the dislike of traction control or power limiting which 
>for
> me is not traction control per se. is the original types of cars that make up 
>this
> sport and the speeds that were possible when this sport was conceived. I 
>suspect,
> but probably am wrong as usual, that when this sport was originally conceived 
>that
> the speeds that seemed possible were in the 175 to 220 range most of the early
> records bear this out, and  there are very few 1950 records that are in the 
>400
> mph range and I am sure that was a speed that was magical and unattainable by 
>the
> competitors in general. The power available was very modest also. To my 
>knowledge
> there were no 700 hp flatheads or Arduns or jimmys around and still aren't any
> either. The average car at Bonneville now probably has that much power and the
> faster cars double that. Now we are going almost twice as fast as originally
> intended or believed possible. Well at 200 most drivers that are competent can
> keep up with the information the car is providing and make appropriate 
>corrections
> before we have an 'event' take place. At 300 the information starts to reach
> overload status and i have no clue how drivers process information at 400+ 
>but i
> am sure whatever the skill level needed to run that speed it can be more than 
>a
> little overwhelming. The power limiting devices to aid in controlling wheel 
>spin
> are mainly to help the driver off load some of this processing so he or she 
>can
> focus on something else. If this is such an alien thought why don't we still 
>have
> an ignition advance lever on the steering wheel it's only one more thing to 
>do. It
> is a good example though of how things electronic or mechanical are used to 
>reduce
> the amount of information the driver has to process and adjust for..
> Same goes for something that will limit the power applied to the wheels
>
> as far as legality goes are any of these things not legal..
> a rev limiter
> boost control
> ignition advance mechanisms (electronic)
>
> I don't recall them being illegal
> so how how can the conditions of operation be illegal??? or even frowned upon.
> I sure hope all the purists pull out their rev limiter, waste gate and 
>ignition
> advance mechanisms...
>
> Dave Dahlgren
>
> Louise Ann Noeth wrote:
>
> > OK, engineer types and racer stars, posit this for me . . .
> >
> > If traction control algorithms has inherent problems due to the undulations
> > and hardness of the salt surface, then would the problem be helped by adding
> > an active suspension system to the mix?
> >
> > And Jack, I can hear you already crabbing about the money, but my thoughts 
>are
> > merely theoretical, not chumming for an agenda, so don't beat me up.
> >
> > Be Vigilant,
> >
> > "LandSpeed" Louise Ann Noeth
> >
> > LandSpeed Productions
> > Telling Stories with Words and Pictures
> > ++++++++++++++++++++++++++++++++++

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