Question? Highest speed recorded in a race

[Jeff Frigo]

Ernie:

You are correct, I read the original article. It was an average speed, not a top speed. I can't find the article, but I believe it was in Road and Track. The car was taped up in order to help with aerodynamics. 234 was the number. It was not at any Nascar track, it was at the high speed oval in Ohio, I think 7 miles long.

[ELGEE]

The glove box door of my cobra is signed"Dick Smith-198 record"-
need more be said?

[RACER X #99]

Well there you go, finally the proof that we have all been looking for. I guess that settles the argument.

Cranky

[Mr.Fixit]

I believe it could have been done. I have never gone over 140 in a cobra, and it was getting light enough I thought it was time to pull up the landing gear. I was actually more afraid that the windshield was going to take my head off. If the driver had the huevos, the car had the power.

[Jamo]

Elgee, Cranky...

[Anthony]

I believe D. Smith went 198.

I remember reading an article about it. Dick just didn't drive his car out on the track, with the same set-up he used for road racing. He knew the car got light at speed, and therefore he lowered the front several inches to give it some rake. He said it still was squirrelly, and he would never drive it that fast again. He also changed the rear gears to 3.07's or 3.23's, or something such that that he topped out at about 7000 rpm's. There were a couple other things he did, but I can't remember them from the article though.


Cal,

friction, or air resistance increases with the square of the speed, so it requires 4 times, not 8 times, the hp to drive the car at 100 mph as compared to 50 mph. The formula holds true with engine rotation and tranny friction with respect to rpm.

Someone talked about weight of the cobra. It is not a factor at a constant speed (top speed). Whether the cobra weighed 1500 lbs or 3000 lbs would not matter, assuming cornering is not limited. However, acceleration, yes, weight makes a difference.

Coefficient of drag , Cd, is a relative number. It really means nothing by itself, only on the relative flow efficiency of a shape in a moving fluid. (car body in air) (submarine in water), etc. To determine the resistance to flow, you take the Cd and multiply it by several factors, one of them the frontal area of the object (car). A boeing 747 probably has a much lower Cd than a jeep, but the overal air resistance at 200 mph is likely higher with the 747 because the cross sectional area is so much greater than a jeep, even though the 747 has with a lower Cd advantage.

If you want to know how to calcualte friction in a moving fluid, I can look it up in one of my engineering books to get all the variables. Some of them are : Cd, cross sectional area, viscosity of fluid, fluid speed, there may be others, but I can't think of them right now.

[Cal Metal]

My reference came from a post written by Bob Putnam. I have a hard time adding 2 plus 2, let alone cubing and squaring numbers. I thought the formula might have some relevance for the mathematicians on the forum relative to the discussion at hand.

[DAVID GAGNARD]

I'am not saying Dick Smith did or did not do 198 in his cobra,but here are some facts I just worked out on one of those rpm-mph calculators.....

Assuming using a four speed transmission with a one to one fourth gear....

7000rpm---29" tall rear tires----3.05 rear end gear=198mph
7000rpm---30" tall rear tires-----3.15 rear end gear=198mph
7000rpm---31" tall rear tires------3.25 rear end gear=198mph
7000rpm---32" tall rear tires------3.36 rear end gear=198mph

This is based on 7000 rpm tops,does not account for clutch slippage or tire slippage if any or wind resistance or drag,just plain mathematical numbers it would take to do this in a perfect world....

If someone had more info such as tire size and rear end gear ratio,that would put things in a different perspective of sorts.....

David

[bonyhadi]

Reading this thread you can see that there are some plain mean spirited people on this forum.

Frankly, the sb vs bb thing to me is just absurd, who cares what you run, you paid for it,
enjoy it. I just switched to a bb and couldn't be happier, no looking back for me. Shelby didn't
come out with the 427 for any reason than he was getting his ass kicked in AP by the Vettes
of Dave McDonald, Guildstrand, Kaplan et al. The move worked and we have the number
one AP Cobra winner in Dick Smith. How many races have you naysayers ran, go ahead and include the ones in your wet dreams for all I care.

What stinks, is to run down a true hero. A guy who loves all Cobra's, even works a rep of sorts for FF5. He is a nice man, always has been, always will be. But the small block fanatics have to try
to disprove something everyone else accepts. Leave Dick Smith alone, have your automotive
accomplishments come close to his? Being a pit gofer doesn't count. All what I see is jealousy,
hatred and damn small people, even if they are 7' tall. Who cares if (BB) you post or don't??

The Shelby history interests all of us, that's why we go to vintage events. But, guess what, there
are dozens of books that state the data just as well, many of us have these books. Some of us
where there as well and saw it first hand.

Jamo and Turk have said it so well, reread their posts on this thread. Shame on you guys!

[Jamo]

Oh just shut up--who cares if you were there and witnessed it?

I'm more interested in trying to figure out when one of those things falls out of her blouse...

Anthony? Gagnard? Can you guys figure out when? Figure normal gravity, the mass of at least 38DDs, the motion dynamics of jogging, etc.

[ecp]

Dick said he ran 3.31 gears with a 27+" rear tire and hit about 8,000 rpm when he was recorded at that speed. Using a 27.5" tire size with .25" assumed growth in dia at speed (a real phenomenon), the speed in fourth gear at 8k = 199.54 mph. Keep in mind this also occured in competition when the cars were new and being thrashed for all they were worth, the adrenaline of beating the next guy in a major form of racing is certainly worth some extra speed. When you also take in consideration that there may have been some draft effect from other cars on the track, and perhaps a little tail wind, 198 is certainly not unreasonable, especially with a number of other dependable reports of original Cobras reaching 180. The fact is that 198 is a documented event and until someone duplicates the exact car on the same track with other cars creating draft and still can't get anywhere near it after repetitive laps, then and only then is it worth any additional effort in checking the validity of the 198 speed.

[bonyhadi]

they pop out all the time, not my fault if you missed it..... I'll edit out the "i was there" stuff
if anyone else complains/////

[Jeff Frigo]

Anthony:

HP is a cubed root, not squared function of speed. 75 hp will get you 100 mph in an average aerodynamic car. If it was squared like you said, it would only take 300 hp to go 200 mph, when in actuality it takes about 600 hp. Just the facts.

[Excaliber]

RacerX quote:
"If we beleive everything we hear or read then Excalibers' claim of 234 by Bill Elliott could become a fact."

See! I told you so, nanny nanny boo boo! LOL

Man you GOT to be careful what you state as FACT in here though! Lot's of sharp minds that are not easily fooled and not afraid to challenge your source! Foggy memory doesn't cut it in this thread!

The original thread WAS: Highest Speed Recorded in a "Race".
OK, so the focus has become Cobras and Dick Smith.

Elliot was not in a "race", so that doesn't count (I guess)? But man his TOP SPEED had to be close to or in excess of 250 mph!!!!

Ernie

[Jamo]

Oinee

Too much poi--seems to me Bonneville is a "race".

[Excaliber]

OH, I SEE, ha ha. SO,,,, if Bonneville is a "race" (and yeah, I guess it is) 198 is not even good enough to "qualify"!

I think it should AT LEAST be a "race track", or better yet a "closed course". Now, is LeMans a "closed course"?

And WHO holds the "closed course" speed record?

Ernie

[Jamo]

Bonneville IS a race track. Turk holds the record for FULL SIZE VAN--BLIND DRIVER. This was accomplished in January, 2002 during KISS Speed Trials. Indicated 100mph. Several witnesses...

[Jamo]

I think the fastest closed circuit/non-race record was Donahue in a Porsche long-tailed 917 in Texas... But I'm probably wrong about that--just something about it sticks with me.

[Anthony]

Jeff, you almost had me. I was second guessing myself. But, there is one advantage I have over you. I stayed at a Marriott last night.



(this paragraph taken from a formula 1 web site)
Another important aspect of aerodynamics is the drag, or resistance, acting on solid bodies moving through air. The drag forces exerted by the air flowing over an airplane, for example, must be overcome by the thrust force developed by the engine. These drag forces can be significantly reduced by streamlining the body. For bodies that are not fully streamlined, the drag force increases approximately with the square of the speed as they move rapidly through the air. The power required, for example, to drive an automobile steadily at medium or high speed is primarily absorbed in overcoming air resistance. The more streamline a vehicle is, the less power it needs to obtain high speeds, and therefore is more economical.


http://hyperphysics.phy-astr.gsu.edu/hbase/airfri.html


Air Drag Coefficients and Frontal Area Calculation
The use of coefficient of drag and frontal area are common when determining horsepower requirements for vehicles in motion. One source of these figures are past issues of Car and Driver or Road and Track magazines. These values can also be determined using the following (obtained from "The ACCELERATOR Slide Rule"):
Coefficient of Drag
The aerodynamic "features" of a vehicle in motion are reflected in its drag coeficient values. Low coefficients indicate low air resistance. The following chart list some ranges for various vehicles, which will suffice when actual measured values are not available:
Vehicle Drag Coefficient
Description Low Medium High
----------------------------------------
Experimental 0.17 0.21 0.23
Sports 0.27 0.31 0.38
Performance 0.32 0.34 0.38
60's Muscle 0.38 0.44 0.50
Sedan 0.34 0.39 0.50
Motorcycle 0.50 0.90 1.00
Truck 0.60 0.90 1.00
Tractor-Trailer 0.60 0.77 1.20
Calculation of Frontal Area
Frontal area represents the front projection area of the vehicle. If one takes a picture of a vehicle, it is the area included in the outline. Use the following to calculate:
1. Calculate the area of a rectangle which would encompass the front of the vehicle (multiply width by the height). For motorcycles, use the handlebar width (to a maximum width of 30 inches) and a height consisting of seat height plus an estimated "seat to helmet" height.
2. Adjust the figure obtained above for areas not included, such as top rounded corners, etc. Typical adjusting values are 85 percent for cars, 70 percent for motorcycles, and 100 percent for trucks.

[Jeff Frigo]

Anthony:

You are correct in that aerodynamic drag is a sqhared function of speed. What I said is that HP is a cube root function.

Quote per Bob Putnam:

"Yup - drag goes up by the square of speed, which means HP is proportional to the cube. It takes 8 times the HP to overcome aerodynamic drag at 100 mph than at 50 mph"

I have read this many times in many publications. Look at the example I gave you. I had a '77 Mustang with a four cylinder, about 75 hp and would go 101 mph, did it many times. If you were correct, a new Corvette could go well over 200 MPH. I'm sorry, but you are wrong. Period.