ET & MPH vs. WT/HP equations?

[70AARCUDA]

I'm doing historical research on drag racing and wonder if anybody recalls the magazine and issue in which the late Roger Huntington first published his "dream wheel" empirical equations for estimating a cars ET and MPH its WT and HP, ie:

MPH = 225*(HP/WT)^(1/3)
ET = 6.29*(WT/HP)^(1/3)

...CAR LIFE magazine has been mentioned, but it's out of business and back-issues impossible to locate.

 

[dcasto]

go here and get the spread sheet for ET and MPH, its cool and you can back trace the equation.

http://www.offroadvw.net

 

[NormPeterson]

I'll have to check to make sure, but I think those empirical equations showed up in a separate softcover book from Hot Rod Magazine, "How To Build a Hot Rod" (circa 1963). What I don't know is whether that was the first time they made it to print.


Norm

 

[70AARCUDA]

...thanks! I'll check the HOT ROD Magazine back issues for that title...I'm writing an article on these empirical equations and wish to "properly / correctly" credit the late Mr. Huntington for his initial work (he was the first to develop such ET and MPH equations) and want to reference his article(s).

...I actually wrote to him once about his articles, but he sadly passed away before I could ask all the questions I had rolling around in my head.

 

[Metalguy]

Those equations are very crude. MPH at the end is strongly influenced by drag/streamlining, and ET by MANY factors beside HP.

Wasn't Roger the guy who predicted that no wheel-driven dragster could ever run in the 8's or go faster than ~160 MPH, because the coef. of friction would have to exceed 1.0? Maybe it was someone else--was a long time ago.

"When the eagles are silent, the parrots begin to jabber."
Winston Churchill

 

[70AARCUDA]

Metalguy -- Yes, that's the same Roger Huntington, but that prediction was made back in the early/mid-1950's, these equations can in the early 1960's...and, were "validated" by Dr. Geoffrey Fox (of Fox Racing) in 1963.

I'm need to know what magazine and issue he first published those equations so that I can "credit" him in my paper.

 

[doug1789]

Hi guys.

I first saw this article in Rod & Custom magazine which I still have somewhere. My friends dad made up a blueprint of the curve and gave me a copy of it. I have looked at that blueprint since Jan. 1958 which I think is the month of the publication (probably read it in December of 1957).

Hope this helps.

 

[NormPeterson]

I thought I was the only one who kept all sorts of old stuff like that.

Anyway, I dug up the "How To Build A Hot Rod" publication and couldn't find it there (although it did present some work involving gearing, engine torque, tire radius, and weight). Now I'm wondering just where I did see it.

Norm

 

[doug1789]

I found the Rod & Custom magazine with Roger Huntingtons aricle about Weight/HP ratio determining Quarter mile speed not E.T. The article is titled "horsepower at the drag strip" page 50, January 1958.

I haven't saved many of my old car magazines, but this one was always special.

Reading some of the other articles from back then reminded me of the sense of adventure of high performance cars for the everyday guy. This article did that for me. Today, awesome engine performance is almost an everyday occurance and the seemingly hidden "laws of performance" are held by fewer of the everyday enthusiast and more and more by the professional team.

Time to join a "Team", I guess.

Regards

 

[70AARCUDA]

doug1789 -- I've e-mailed ROD & CUSTOM (Primera) asking for a copy of that article, BUT if I'm not successful, would it be possible to obtain a copy from you (of just THAT article, nothing else)?

Did you also read HOT ROD MAGAZINE circa 8/73, 11/73. 3/74 and/or HOT ROD YEARBOOK No. 14? especially the "Auto Shop" articles: "Basic Engine Physics & Math", "Drag Strip Dyno", "Header Science" and "Budget-Building the MOPAR 318."

 

[doug1789]

Yes, I am willing to help in any way I can. The mentioned Yearbook and article dates don't ring a bell. I have seen and read various articles over the years and some software programs seem to be using this concept of Lb/HP to give their estimates of Q. mile terminal velocity. Accelerometer readings seem to be more practical today and are probably more accurate. It's all fascinating to me still.

But how do we communicate without including email addresses or phone numbers? I'm in Northern California. Let me know what you want me to do.

Doug.

 

[NormPeterson]

Doug - may I suggest membership in the same separate bulletin board. Preferably a busy one.

If it helps either of you, I almost certainly have the '73 and '74 magazines (but not the 14th Yearbook). Just PM or e-mail me through

http://www mustangforums

com (you'll probably have to register first).


Norm

 

[70AARCUDA]

doug1789 & NormPeterson -- Thanks guys. I'll first see if Primedia can get me a copy of that Huntington article, but if they can't, then I'll take you up on your offer.

As for those HOT ROD articles, I'm the author...and "Drag Strip Dyno" was *my* attempt at a physics-based empirical equation for estimating 1/4-mile MPH & ET against vehicle HP & WT.

At the time, I didn't know of Huntington's article, so I was basically "re-inventing" his work, but I did know about H&H Racing's phamphlet with equations, and had collected lots of NHRA MPH and ET numbers to work with. Much later, I came across Dr. Geoffrey Fox's article which verified the basis of Huntington's equations.

 

[plasgears]

Wt/HP should be modified to Wt/HP^0.5. Dividing by the square root of power is a better group.

In aviation studies doubling the HP does not double the speed. A helpful group in planes is max speed divided by the square root of power. This rates the 'efficiency' of power to produce speed. Of course weight, drag and other parameters are buried in the group.

 

[70AARCUDA]

OK, doug1789, looks like the "current" ROD & CUSTOM magazine/PRIMEDIA don't go back that far, so, "pretty please," if possible I'd appreciate getting a copy of that Roger Huntington article from January 1958 from you...

...now, comes the question of "how to" get it done?

...since WE'RE both 'electrical' maybe a "common" external website will help? -- have you ever looked over some of the offerings at PENTODE PRESS? Some of my vacuum tube articles are posted there under "Vacuum Tube Archeology" and the AUTHOR page has a hotlink to my home e-mail.

...FWIW Jeff Lucius' STEALTH316 website has a separate page ("1/4-mile and HP") on these equations entitled: "Calculators for 1/4-Mile ET & MPH vs. HP and Weight."

 

[evelrod]

Norm,

The only 'math' equations in the 1963 Hot Rod Publication's "How to Build a Hot Rod" are simple power/weight and speed/gear ratio stuff by OCee Ritch. (I still have a copy).

Doug,

I do recall the "mystery math" from Huntington in the late 50's as I started drag racing my 49 Merc gasser in '58 and read all that I could on the subject. If I can still remember that far back, we, the engineering school hot rod fraternity, thought it a bunch of 'hogwash'...I still do.

Rod

 

[70AARCUDA]

...many "Thanks" to doug1789 for sending me a copy of Roger Huntingtons' ROD & CUSTOM article, "Horsepower at the Drag Strip," December 1958, pages 50-53!

...although Huntington does NOT specifically mention his empirical equation in the article, ie: MPH = 224*(HP/WT)^(1/3), backsolving the graph and example car values, yields his approximated equation.

...interestingly, when a POWER regression analysis is applied to the example values, this is the result:

MPH = 235.85*(HP/WT)^(0.3523) ...with R^2 = 0.9995

...values commonly used today...but Roger's number crunching was done on a slide-rule, not a home computer!