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Conference napalm::musclecars

Title:Musclecars
Notice:Noter Registration - Note 5
Moderator:KDX200::COOPER
Created:Mon Mar 11 1991
Last Modified:Mon Jun 02 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:182
Total number of notes:5467

104.0. "Hot Rod Math" by EEMELI::HAKALA (Tuomo Hakala, T&C Open Systems, Finland) Sun Apr 11 1993 06:26

    Howdy!
    
    
    
    
    
    		Is anyone interested in hot rod math?  I just read some
    interesting formulas from an finnish book about performance.  Not so
    sure whether they correct or not, so please try them and compare the
    results to the real ETs.  And please, keep us posted.
    
    
    
    		FORMULA 1: horsepower from ET
    
    
    	   		        166.55
    			hp = ------------ *  mass (pounds)
    			     ET * ET * ET
    
    
    		FORMULA 2: ET from horsepower (derived from F1)
    
    
    			    166.55
    			X = ------ * mass
    			      hp
                
    			ET = cubic root of X
    
    
    		FORMULA 3: hp from ending speed
    
    
    			X = 0.004259 * speed (mph)
    
    			hp = X * X * X * mass
    
    
    		FORMULA 4: ending speed from hp (derived from F3)
    
    
    			     hp
    			X = ----
    			    mass
    
                                   1
    			speed = -------- * cubic root of X
                             	0.004259
T.RTitleUserPersonal
Name		DateLines
104.1NOVA::FISHERDEC Rdb/DinosaurMon Apr 12 1993 06:203
    It ignores air resistance.
    
    ed
104.2No it doesn'tSANTEE::AUGENSTEINMon Apr 12 1993 08:3434
What it *does* do is take a bunch of things into account that it more
or less averages over a lot of cars.

I personally think formulas that compute HP from ET are pretty nearly
worthless, since traction and gearing can have major effect on an average
ET. However, terminal speed is a very good indicator of HP, almost regardless
of traction and gearing.

Measured between various street cars, aerodynamics doesn't have a major effect,
since a 15 second run means you're only averaging 60 mph for the duration.
As an example of a significant difference, a late Mustang, with a fairly big
frontal area and lousy aerodynamics, will go around 1 mph slower than a late
Vette (with smaller frontal area and good aerodynamics), with the *same* power
to weight ratio. This is not a big difference. (Note: I am using QUARTER
software to "prove" this.)

Gearing doesn't have a major effect, either. You can "prove" this by plotting
torque at the drive wheels on an X-Y graph (assuming you know the power curve)
from zero to whatever MPH, using first gear through whatever gear. Then do it
again after changing (on paper) the final drive ratio. You will see that the
"area under the curve" showing available torque throughout the speed range
doesn't change much at all. An example would be, again, a late Mustang. Going
from 3.08s to 3.55s gets you about 1/2 MPH - no more. Of course, there may be
significant differences in potential ET between 3.08s and 3.55s (depending on
traction), which is one of the key reasons I don't think ET/HP calculations are
worth anything.

As to the MPH/HP formulas mentioned in the base note, they appear to be around
3% more conservative than the formula outlined in 8.356, possibly because we
may be comparing SAE and DIN measurements. No matter. What is most important is
that the fomulas give you a base against which to measure your modifications,
and their relative worth.

Bruce
104.3Engine displacement informationTINCUP::MFORBESIt's NOT your father's Chevy VegaMon May 23 1994 14:41397
I found the following out on the Internet in rec.autos.rod-n-custom and thought
that it might be of interest to the readership of this Notesfile.

Mark

--------------------------------------------------------------------------------
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From: [email protected] (Ron Gregory)
Subject: Engine size FAQ
Message-ID: <[email protected]>
Sender: [email protected]
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Date: Mon, 23 May 1994 16:27:59 GMT
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I want to try to solve some problems.  I got out my Standard
Catalog of American Cars and copied some numbers into 1-2-3,
and viola!  We now have the beginnings of an engine size FAQ :)

I didn't go back to the 1950's, so you may not see some older 
engine sizes in here.  If it's really important to you, let me know.

My book only goes to 1975, so some of the newer engines are not here
either,  I need some help.

If any of these are wrong, I'm sorry.  Instead of flaming me, why
don't you just E-mail me the correct numbers.  Thanks.

I couldn't find the bore and stroke (B&S) of the chevy 400 small block,
or the chevy 454.  If you don't find your favorite motor here, let me know.  
Can you help complete this list?  (via E-mail, please)

Also, the book did not always state if the 6-cyl engines were in-line of V6.
Can I get some help there, too?

Thanks,

-Ron
---- Begin list ---

Formulas I am using
--------------------

volume of a cylinder = r^2*pi*h = (bore / 2) ^ 2 * pi * stroke
value of pi: 3.141592653587973 (close enough)
Cubic centimeters in a cubic inch: 2.54 * 2.54 * 2.54 = 16.387064

Your favorite motor 
(dimensions courtesy Standard Catalog of American Cars)
-------------------
Ford's 170 6-cyl:
bore			: 3.5
stroke			: 2.94
cubic inches		: 169.716689
cubic centimeters	: 2781.158247

Chrysler's 198 Slant 6:
bore			: 3.40
stroke			: 3.64
cubic inches		: 198.289788
cubic centimeters	: 3249.387454

Ford's 200 6-cyl:
bore			: 3.68
stroke			: 3.13
cubic inches		: 199.747387
cubic centimeters	: 3273.273213

Pontiac's 215 6-cyl:
bore			: 3.75
stroke			: 3.25
cubic inches		: 215.370903
cubic centimeters	: 3529.296765

Ford's 223 6-cyl:
bore			: 3.62
stroke			: 3.6
cubic inches		: 222.310909
cubic centimeters	: 3643.023086

Chrysler's 225 Slant 6:
bore			: 3.41
stroke			: 4.13
cubic inches		: 226.308018
cubic centimeters	: 3708.523977

Buick's 231 V6:
bore			: 3.80
stroke			: 3.40
cubic inches		: 231.359449
cubic centimeters	: 3791.302104

Ford's 240 6-cyl:
bore			: 4.00
stroke			: 3.18
cubic inches		: 239.766351
cubic centimeters	: 3929.066544

Buick's 250 L6:
bore			: 3.87
stroke			: 3.5
cubic inches		: 247.019425
cubic centimeters	: 4047.923124

Ford's 250 6-cyl:
bore			: 3.68
stroke			: 3.91
cubic inches		: 249.524691
cubic centimeters	: 4088.977081

Oldsmobile's 250 L6:
bore			: 3.875
stroke			: 3.53
cubic inches		: 249.780914
cubic centimeters	: 4093.175827

Ford's 260 V8:
bore			: 3.8
stroke			: 2.87
cubic inches		: 260.392792
cubic centimeters	: 4267.073348

Buick's 260 V8:
bore			: 3.5
stroke			: 3.385
cubic inches		: 260.540133
cubic centimeters	: 4269.48783

Chevy's 283 V8:
bore			: 3.875
stroke			: 3.00
cubic inches		: 283.037863
cubic centimeters	: 4638.159578

Ford's 289 V8:
bore			: 4.00
stroke			: 2.87
cubic inches		: 288.523869
cubic centimeters	: 4728.059112

Ford's 300 V6:
bore			: 4.00
stroke			: 4.00
cubic inches		: 301.592895
cubic centimeters	: 4942.222068

Ford's 302 V8:
bore			: 4.00
stroke			: 3.00
cubic inches		: 301.592895
cubic centimeters	: 4942.222068

Chevy's 307 V8:
bore			: 3.875
stroke			: 3.25
cubic inches		: 306.624352
cubic centimeters	: 5024.672876

Chrysler's 318 V8:
bore			: 3.91
stroke			: 3.31
cubic inches		: 317.951865
cubic centimeters	: 5210.297563

Chevy's 327 V8:
bore			: 4.00
stroke			: 3.25
cubic inches		: 326.725636
cubic centimeters	: 5354.073907

Oldsmobile's 330 V8:
bore			: 3.939
stroke			: 3.39
cubic inches		: 330.484829
cubic centimeters	: 5415.676048

Chrysler's 340 V8:
bore			: 4.04
stroke			: 3.31
cubic inches		: 339.445919
cubic centimeters	: 5562.522007

Chevy's 350 V8:
bore			: 4.00
stroke			: 3.48
cubic inches		: 349.84758
cubic centimeters	: 5732.977599

Buick's 350 V8:
bore			: 3.8
stroke			: 3.85
cubic inches		: 349.307404
cubic centimeters	: 5724.122784

Oldsmobile's 350 V8:
bore			: 4.057
stroke			: 3.385
cubic inches		: 350.064891
cubic centimeters	: 5736.535779

Ford's 351 V8:
bore			: 4.00
stroke			: 3.50
cubic inches		: 351.858377
cubic centimeters	: 5765.925746

Chrysler's 360 V8:
bore			: 4.00
stroke			: 3.58
cubic inches		: 359.900854
cubic centimeters	: 5897.718335

Chrysler's 383 V8:
bore			: 4.25
stroke			: 3.375
cubic inches		: 383.028867
cubic centimeters	: 6276.718554

Pontiac's 389 V8:
bore			: 4.06
stroke			: 3.75
cubic inches		: 388.385675
cubic centimeters	: 6364.500913

Ford's 390 V8:
bore			: 4.05
stroke			: 3.78
cubic inches		: 389.841995
cubic centimeters	: 6535.849296

Oldsmobile's 394 V8:
bore			: 4.125
stroke			: 3.6875
cubic inches		: 394.239198
cubic centimeters	: 9460.422976

Chevy's 396 V8:
bore			: 4.094
stroke			: 3.76
cubic inches		: 395.971009
cubic centimeters	: 6488.802262

Chrylser's 400 V8:
bore			: 4.34
stroke			: 3.375
cubic inches		: 399.423032
cubic centimeters	: 6545.370796

Buick's 400 V8:
bore			: 4.18
stroke			: 3.64
cubic inches		: 399.607670
cubic centimeters	: 6548.396465

Oldsmobile's 400 V8:
bore			: 3.87
stroke			: 4.25
cubic inches		: 399.936212
cubic centimeters	: 6553.780296

Pontiac's 400 V8:
bore			: 4.125
stroke			: 3.746
cubic inches		: 400.493569
cubic centimeters	: 6562.913754

Chevy's 400 V8:
bore			: 4.125
stroke			: 3.75
cubic inches		: 400.921219
cubic centimeters	: 6569.92167

Chevy's 400 V8 (small block):
bore			: 
stroke			: 3.48
cubic inches		: 
cubic centimeters	: 

Ford's 400 V8:
bore			: 4.00
stroke			: 4.00
cubic inches		: 402.123860
cubic centimeters	: 6589.629424

Chrysler's 413 V8:
bore			: 4.188
stroke			: 3.75
cubic inches		: 413.261057
cubic centimeters	: 6772.135389

Ford's 427 V8:
bore			: 4.23
stroke			: 3.78
cubic inches		: 424.964256
cubic centimeters	: 6963.916463

Oldsmobile's 425 V8:
bore			: 4.125
stroke			: 3.975
cubic inches		: 424.976492
cubic centimeters	: 6964.11697

Chrysler's 426 V8:
bore			: 4.25
stroke			: 3.75
cubic inches		: 425.587630
cubic centimeters	: 6974.131727

Ford's 428 V8:
bore			: 4.13
stroke			: 3.98
cubic inches		: 426.543221
cubic centimeters	: 6989.791055

Buick's 430 V8:
bore			: 4.18
stroke			: 3.9
cubic inches		: 428.151075
cubic centimeters	: 7016.13907

Ford's 429 V8:
bore			: 4.36
stroke			: 3.59
cubic inches		: 428.792614
cubic centimeters	: 7026.652

Chrysler's 440 V8:
bore			: 4.326
stroke			: 3.75
cubic inches		: 440.944740
cubic centimeters	: 7225.789675

Chevy's 454 V8:
bore			:
stroke			:
cubic inches		:
cubic centimeters	:

Oldsmobile's 455 V8:
bore			: 4.125
stroke			: 4.250
cubic inches		: 454.377381
cubic centimeters	: 7445.911226

Pontiac's 455 V8:
bore			: 4.15
stroke			: 4.21
cubic inches		: 455.573189
cubic centimeters	: 7465.507008

Buick's 455 V8:
bore			: 4.313
stroke			: 3.9
cubic inches		: 455.830511
cubic centimeters	: 7469.723763

Ford's 460 V8:
bore			: 4.36
stroke			: 3.85
cubic inches		: 459.847232
cubic centimeters	: 7535.546017

Cadillac's 472 V8:
bore			: 4.3
stroke			: 4.06
cubic inches		: 471.674951
cubic centimeters	: 7729.367611

Cadillac's 500 V8:
bore			: 4.3
stroke			: 4.304
cubic inches		: 500.021919
cubic centimeters	: 8193.891182


_____________________________________________________________________
     _______                     _________        Ron Gregory
    /\______\                   /\________\       [email protected]
   / / ___  /_____ _______     / / _______/ 
  / / /_\/ /______\\______\   / / / /\___\        Texas Instruments, Inc
 / / _  __// ___  // ___  /  / / /__\/_  / __     Plano, TX
/ / / \ \ / /_\/ // /  / /  / / /_____/ / /\_\
\/_/   \_\\_____//_/ \/_/   \/_________/  \/_/    (214) 575-4962
Not responsible for the actions of the spelling gremlins...
Opinions of the author are rarely those of TI.
--------------------------------------------------------------------
104.4He'll get mail, I'm sure.VMSNET::M_MACIOLEKFour54 Camaro/Only way to flyMon May 23 1994 20:136
    Oh dear, .-1 _doesn't know the specs on a 454 Chevy?
    Bore: 4.25/Stroke 4.00.
    
    FWIW: The 400 is 4 1/8" by 3.75 stroke"
    
    MadMike