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Author Topic: Ballast increases thrust. DOESN'T give tires more grip.  (Read 11127 times)

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Franklin_Ratliff

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Ballast increases thrust. DOESN'T give tires more grip.
« on: November 19, 2005, 11:47:34 AM »
In designing the first car to clock 400 mph (John Cobb's) Reid Railton used a traction coefficient of about .50 for his calculations.

A traction coefficient of .50 means a tire CANNOT develop a forward thrust equal to more than 50% of the load pressing down on it. Adding ballast simply increases thrust. It DOESN'T give the tires more grip.

This means if you put a g-meter on any bike or car running at Bonneville you won't find a single one accelerating at more than about half a g.

On dirt a tireless wheel has a traction coefficient of about .30.

Tireless wheels haven't worked in wheel-driven applications at Bonneville not because they can't get traction, but because salt sticks to them until a speed of about 200 mph is reached, at which point centrifugal force spins off the salt, allowing the wheel to get a grip. This is why the Budweiser rocket car and Richard Noble's Thrust 2 jet car were able to brake at Bonneville without locking up the wheels.
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Offline 1212FBGS

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Ballast increases thrust. DOESN'T give tires more grip.
« Reply #1 on: November 20, 2005, 01:17:24 PM »
explain to me how can you say that "ballast increases thrust"
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Offline John Burk

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Ballast increases thrust. DOESN'T give tires more grip.
« Reply #2 on: November 21, 2005, 02:27:00 AM »
Ballast can make a car easier to drive , it can overcome lift and it can make a car less likely to spin . Unless there is wheel spin in high gear adding weight has the same effect as lowering horse power .
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rosemeyer

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Ballast increases thrust. DOESN'T give tires more grip.
« Reply #3 on: November 21, 2005, 08:43:21 AM »
"...ballast... It DOESN'T give more grip"

FR

How can you explain that?
Is it that everybody has got it wrong for so long?

My understanding is that land racer use ballast TO GET MORE grip (when needed) without compromising aerodynamics.

Circuit racing cars use wings, to get downforce without adding static weight; top speed is less important to them.

In both cases, both play with added weight TO GET MORE GRIP.
Did I get that completely wrong, then...

Remember the Pirelli advert? "Power is nothing without control"
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Franklin_Ratliff

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Simple Physics
« Reply #4 on: November 21, 2005, 11:16:25 AM »
Quote from: rosemeyer
"...ballast... It DOESN'T give more grip"

FR

How can you explain that?
Is it that everybody has got it wrong for so long?

My understanding is that land racer use ballast TO GET MORE grip (when needed) without compromising aerodynamics.

Circuit racing cars use wings, to get downforce without adding static weight; top speed is less important to them.

In both cases, both play with added weight TO GET MORE GRIP.
Did I get that completely wrong, then...

Remember the Pirelli advert? "Power is nothing without control"


Because, Sherlock, 50% of MORE weight (MORE LOAD PRESSING DOWN ON THE TIRE) is MORE thrust. "A traction coefficient of .50 means a tire CANNOT develop a forward thrust equal to more than 50% of the load pressing down on it. Adding ballast simply increases thrust. It DOESN'T give the tires more grip." DO THE MATH.
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Franklin_Ratliff

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Simple Physics
« Reply #5 on: November 21, 2005, 11:16:22 AM »
Quote from: rosemeyer
"...ballast... It DOESN'T give more grip"

FR

How can you explain that?
Is it that everybody has got it wrong for so long?

My understanding is that land racer use ballast TO GET MORE grip (when needed) without compromising aerodynamics.

Circuit racing cars use wings, to get downforce without adding static weight; top speed is less important to them.

In both cases, both play with added weight TO GET MORE GRIP.
Did I get that completely wrong, then...

Remember the Pirelli advert? "Power is nothing without control"


Because, Sherlock, 50% of MORE weight (MORE LOAD PRESSING DOWN ON THE TIRE) is MORE thrust. "A traction coefficient of .50 means a tire CANNOT develop a forward thrust equal to more than 50% of the load pressing down on it. Adding ballast simply increases thrust. It DOESN'T give the tires more grip." DO THE MATH.
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Franklin_Ratliff

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Simple Physics
« Reply #6 on: November 21, 2005, 11:16:53 AM »
Quote from: rosemeyer
"...ballast... It DOESN'T give more grip"

FR

How can you explain that?
Is it that everybody has got it wrong for so long?

My understanding is that land racer use ballast TO GET MORE grip (when needed) without compromising aerodynamics.

Circuit racing cars use wings, to get downforce without adding static weight; top speed is less important to them.

In both cases, both play with added weight TO GET MORE GRIP.
Did I get that completely wrong, then...

Remember the Pirelli advert? "Power is nothing without control"


Because, Sherlock, 50% of MORE weight (MORE LOAD PRESSING DOWN ON THE TIRE) is MORE thrust. "A traction coefficient of .50 means a tire CANNOT develop a forward thrust equal to more than 50% of the load pressing down on it. Adding ballast simply increases thrust. It DOESN'T give the tires more grip." DO THE MATH.
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Franklin_Ratliff

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Simple Physics
« Reply #7 on: November 21, 2005, 11:22:24 AM »
Quote from: rosemeyer
"...ballast... It DOESN'T give more grip"

FR

How can you explain that?
Is it that everybody has got it wrong for so long?

My understanding is that land racer use ballast TO GET MORE grip (when needed) without compromising aerodynamics.

Circuit racing cars use wings, to get downforce without adding static weight; top speed is less important to them.

In both cases, both play with added weight TO GET MORE GRIP.
Did I get that completely wrong, then...

Remember the Pirelli advert? "Power is nothing without control"


Because, Sherlock, 50% of MORE weight (MORE LOAD PRESSING DOWN ON THE TIRE) is MORE thrust. "A traction coefficient of .50 means a tire CANNOT develop a forward thrust equal to more than 50% of the load pressing down on it. Adding ballast simply increases thrust. It DOESN'T give the tires more grip." DO THE MATH.
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SALTRACER

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Ballast increases thrust. DOESN'T give tires more grip.
« Reply #8 on: November 21, 2005, 11:40:15 AM »
What web page did you copy and past this info from.  I know you didn't come up with this by yourself!!!!!!!! :twisted:  :twisted:  :twisted:
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Franklin_Ratliff

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Ignorant D U M B S H I T S
« Reply #9 on: November 21, 2005, 11:52:54 AM »
Quote from: SALTRACER
What web page did you copy and past this info from.  I know you didn't come up with this by yourself!!!!!!!! :twisted:  :twisted:  :twisted:


Because, UNLIKE MORONS LIKE YOU, 30 years ago I read the article by Roger Huntington in Hot Rod published over 40 years ago about the proposed design for Alex Tremulis' "Gyronaut" car.
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SALTRACER

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Ballast increases thrust. DOESN'T give tires more grip.
« Reply #10 on: November 21, 2005, 12:08:14 PM »
Wow forty years ago huh!!!!!! Why don't you just copy and past it so we can see how smart you are.
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Franklin_Ratliff

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Morons
« Reply #11 on: November 21, 2005, 12:56:41 PM »
Back in the thirties Reid Railton designed cars that set land speed records at Daytona Beach and Bonneville, as well as the first cars to run 300 mph and 400 mph. I'd say he knew a few things about traction. How STUPID does a person to be and BIG an ego do they need to have before they think they understand traction better than Reid Railton?
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SALTRACER

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Ballast increases thrust. DOESN'T give tires more grip.
« Reply #12 on: November 21, 2005, 01:42:37 PM »
I don't understant it better than he does, but you don't either.  Get a life Frank.
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Offline 1212FBGS

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Ballast increases thrust. DOESN'T give tires more grip.
« Reply #13 on: November 21, 2005, 01:42:38 PM »
Ok Frank I am trying to figure this out. I am not a physics guy or college educated and not trying to slam you.  If I understand your post, you claim that added weight cannot increase traction, but how can you increase thrust if the added weight is not increasing grip or traction to gain forward momentum. In every racing format I have been involved in other than LSR, weight (mass) reduction is critical.
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Offline Salty Blaster

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Ballast increases thrust. DOESN'T give tires more grip.
« Reply #14 on: November 21, 2005, 01:49:03 PM »
Hey Rat

Any original thoughts of your own? Like, how you applied other racers knowledge and experience to your own racing efforts at Bonneville? I for one would be interested in how you used these on the salt and what your results were / are?

I'm ready to be enlightened.
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Go faster, just don't eat the salt!
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