Useful Calculators

[Injected]

I was thinking about the DSM Quiz idea I had a while back so newbs could graduate beyond the rookie level We'll I wrote a script based on a spreadsheet I have been using for a while so I could easily send it to friends for them to use since some people have a fear of spreadsheets. Anyhow, I thought I would throw it out there for you guys to take a look at and see if it is something that you would be interested in for the site. Sections could help people with some questions they may have regarding power potential, tire size, etc. Many of the variables are automatically loaded for those who may not know their intercooler pressure drop, and changeable for those who do. As of now, the calculators on this page do not function. HOWEVER, the WORKING scripts are available for you to download after the calculators. (See below).

Navigation

Use these links to navigate the calculators.

1. Compressor Map Tool / Horsepower Potential Estimator

2. Intake Temperature Calculator

3. Airflow Converter (lb/min to CFM)

4. Airflow Converter (CFM to lb/min)

5. Injector Size Calculator

6. Power from Trap Speed Estimator

7. 1/4 mile ET and Trap Speed from Power Estimator

8. Engine Displacement Calculator

9. Engine Displacement Converter (cc to ci)

10. Engine Displacement Converter (ci to cc)

11. Tire Diameter Calculator

12. Rotational Mass Equivalency Calculator

Turbo Power Estimator and Compressor Map Tool
This calculator uses the amount of air and fuel flowed and calculates the amount of horsepower created by burning that air/fuel mixture.
Variable		Input
Engine Displacement (cubic inches)
Desired Boost (psi)
Desired Engine RPM (redline or shift point)
Intake Temperature (Post Intercooler if applicable; °F)
Intercooler Pressure Drop (psi)
Air Fuel Ratio		:1
Volumetric Efficiency (est. 90% for DOHC 4 valves per cylinder)		%
Brake Specific Fuel Consumption (BSFC)
Using the following two numbers given from the calculator above, you should be able to use a compressor map to select the turbo that best fits your desired power goals.
Variables for Compressor Maps:	CMf:	Pr:

Back to Navigation

Intake Temperature Calculator
This calculator will calculate the intake temperature based on the compressor and intercooler.
Variable	Input
Turbo Inlet Temperature (Consider inlet pipe and filter location)
Turbo Inlet Pressure (psi: filtered:~13.95; open:~14.7; -0.5psi/1000ft elev.)
Boost (psi)
Compressor Efficiency (Map Pr and CMf on compressor map)
Intercooler Efficiency (%)
Intercooler Pressure Drop (psi)
Ambient Temperature (outside the engine bay °F)
	----------
Intercooler Inlet Temperature
Intercooler Outlet/Intake Temperaturev

Back to Navigation

Airflow Convertor (lb/min to CFM)
This calculator will convert airflow rates from pounds per min to cubic feet per minute.
Variable	Input
Airflow (lb/min)

Back to Navigation

Airflow Convertor (CFM to lb/min)
This calculator will convert airflow rates from cubic feet per minute to pounds per minute.
Variable	Input
Airflow (lb/min)

Back to Navigation

Injector Size Calculator
This calculator will allow you to calculate the needed injector size for you to support a specified horsepower at the injector duty cycle.
Variable		Input
Engine Horsepower
Number of Injectors		4 6 8 10 12
BSFC
Injector Duty Cycle
	Lb/Hr	cc/min

Back to Navigation

Estimate Power from 1/4 mile Trap Speed
This calculator uses a modified version of Force=Mass*Acceleration to calculate how much power it would take to make your car go a certain speed by the end of a quarter mile.
Variable		Input
Vehicle Weight (Including driver)
1/4 mile MPH
Select Drivetrain:   AWDFWD

Back to Navigation

Estimate ET and Trap Speed from Horsepower
This calculator uses a modified version of Force=Mass*Acceleration to calculate how fast a car with the given power and weight would take to lay waste to a quarter mile.
Variable		Input
Vehicle Weight (Including driver)
Wheel Horsepower
	@

Back to Navigation

Engine Displacement Calculator
This calculator will determine the displacement in cc's of an engine based on the bore, stroke, and number of cylinders.
Variable	Input
Bore (mm)
Stroke (mm)
Number of Cylinders	4 6 8 10 12

Back to Navigation

Engine Displacement Converter (cc to ci)
This calculator will convert cubic centimeters to cubic inches.
Variable	Input
Displacement (cc)

Back to Navigation

Engine Displacement Converter (ci to cc)
This calculator will convert cubic inches to cubic centimeters.
Variable	Input
Displacement (ci)

Back to Navigation

Tire Diameter Calculator
A tire with a larger diameter will make your speedometer read slower than you are going and a tire with a smaller diameter will make your speedometer read faster than you are going. In addition, a tire with a larger diameter will take more power to rotate.
Variable	Input
Tire size example: 215/55/17

Back to Navigation

Equivalent Mass of a Rotating Object Calculator
This calculator will calculate the affect of taking weight off the engines rotating assembly as multiplied through the gears. This includes flywheels, pulleys, etc. prior to the transmission.
Variable		Input
Change in rotating mass
Diameter of rotating object
Weight equivalency in first:	First Gear :1
Weight equivalency in second:	Second Gear :1
Weight equivalency in third:	Third Gear :1
Weight equivalency in fourth:	Fourth Gear :1
Weight equivalency in fifth:	Fifth Gear :1
Final Drive ratio	Final Drive :1	----------
Tire Diameter (Use calculator if needed)	inches	----------
		----------

As for the script, well you can download it in the .doc file found later on in the thread, paste the text into notepad, save as .html and play with the fully functioning version. There have already been users who have downloaded this and earlier versions successfully. If you have a problem, please address it in this thread: http://www.dsmtuners.com/forums/showthread.php?t=225473 . I am working to get a working version on the site.