Motorsports Standard Atmosphere and Weather Correction Methods
By Patrick Hale
Kind of a long title but basically it's Everything you ever wanted to know about weather and
racing. I just call it the Racing Weather Book.
Patrick Hale is the inventor of one of the first "what if" programs, the popular Quarter Jr
and the Density weather tuning program. He has now written the definitive book on
weather and race cars.
Did you buy a fancy weather station but always wondered what all that stuff meant?
Could you do a better job of tuning if you knew what all that stuff meant?
Are you a glutton for punishment and want to know all the math behind those programs?
It's all in this book. Just look at the Table of Contents below. Clear explanations of every
part of weather and how it relates to tuning. Every bit of math is also in here so you can
make up your own spreadsheet if desired. Works with gas, alcohol or nitromethane! There's
even quite of bit of information on adjusting (correction factors) for things like weight,
aerodynamics, track temps, down hill race tracks, etc.
Why did he do this since you can create your own Density program with the information
provided? Because he can and plus no one has ever sat down and put it into perspective
relative to race cars before. Sad but true. We have all seen bits and pieces in magazines
but they often didn't agree with each other and confused us even further. I suspect that
there are very few individuals that grasp every part of weather versus racing and it's
importance. Patrick Hale is one of them.
The book is a good read, written clearly and in racing terms. I read through it again last
night and finally know why I could never get my density altitude calcs to match his exactly.
There are many methods and no one seems to agree, including airplane people. Now it's
finally all in one place with sample calculations to guide you.
2008..... Weather Book ...... $49.00
IL residents: No sales tax on this item.
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Urbana, IL USA 217-531-1770 M- F 9-5 CST
Table of Contents
Variable Names and Descriptions
Calclulated or Derived Constants
Chapter 1 - Introduction
About the Author
About the Book
Chapter 2 - Motorsports Standard Atmosphere
Standard Air Density at Sea Level
Chapter 3 - MSA Temperature Definition
ISA Temperature Definition
MSA Temperature Definition
MSA Temperature Table
Chapter 4 - MSA Pressure Definition
Perfect Gas Law
ISA Pressure Definition
ISA Pressure Table
MSA Pressure Definition
MSA Pressure Table
Chapter 5 - Measuring Ambient Pressure
Chapter 6 - Density Altitude
Air Density Index for Dry Air
Air Density Index (complete)
Density Altitude Equation
Density Altitude Table
Chapter 7 - How much Water is in the Air?
Three Devices for Measuring Water Vapor Content
Describing Water Vapor Content
Relative Humidity Chart
Saturation Pressure Formula
Real World Mathematical Weather Examples
High Water Vapor Content Example
Chapter 8 - SAE Horsepower Correction
The "problem" with Density Altitude
HP Correction Factor
Sample HP Correction Factor Equation
Definition of Theta and Delta
Comprehensive Weather Examples
Chapter - 9 General HP Correction Factor Equation
Sample HPC Equation for Methanol
Sample HPC Equation for Blown Nitro
Other Weather Correction Factors
Chapter 10 - Drag Racing ET and MPH Weather and Weight Corrections
ET Correction Methods
MPH Correction Methods
Weight Correction Methods
Combined HPC and Weight Correction Methods
Dragstrip Dyno Update
Chapter 11 - Drag Racing ET and MPH Track Corrections
Downhill Racetrack Correction Methods
Track Temperature Correction Methods
Chapter 12 - Drag Racing ET and MPH Wind Corrections
Head Wind Correction Methods
Other Wind Angle Correction Methods
Chapter 13 - Closing
Brackets Quick 8 Top Dragster / Sportsman ProMod Super Gas / Comp 10.5 Sand Mud Pulling