Calculating an engine's camshaft requirements
From Crankshaft Coalition Wiki
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− | Yes, there is and has been an equation that calculates an engine's camshaft requirement, with an accuracy of +/- 1%. You may not believe it, but it is true and it doesn't require a college degree to understand. It was written | + | Yes, there is and has been an equation that calculates an engine's camshaft requirement, with an accuracy of +/- 1%. You may not believe it, but it is true and it doesn't require a college degree to understand. It was originally written by Ed Winfield, in the late 1940's. and was revised in 1977, by the four time INDY 500 winning engine designer and builder, Dick Jones. Dick was the Technical Racing Manager for Champion Spark Plug Company, in charge of their West Coast Engine Dyno Facility for close to 30 years. These formulas have been used by many of the industries premiere engine builders, aftermarket parts manufacturers and two or three cam companies. The math has been qualified as a true equation by two separate college professors, and verified by an automotive engineer with a PhD in Fluid Mechanics/Dynamics. |
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− | Here are the basic | + | The equation is built on, and describes, the mathematical relationships of the engine parameters, operating variables and performance. The equation can solve for, or be solved by, any of the related parameters, including the camshaft. The equation calculates the valve opening lift curve, required by the effective port area, to fill the given cylinder the desired V.E.%, at the requested RPM. |
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+ | Here are some of the basic principals of the equation: | ||
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• The bore and the stroke dictate the cylinder volume. | • The bore and the stroke dictate the cylinder volume. | ||
• The rate of volume is dictated by the cylinder volume and RPM at Maximum HP. | • The rate of volume is dictated by the cylinder volume and RPM at Maximum HP. | ||
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• The effective port area is calculated from the available intake port flow CFM. | • The effective port area is calculated from the available intake port flow CFM. | ||
• The relationship between the port area required and the effective port area determines the net intake valve lift. | • The relationship between the port area required and the effective port area determines the net intake valve lift. | ||
− | • The relationship between | + | • The relationship between Mean Piston and Mean Port Velocity determines the req. intake valve seat duration. |
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+ | If you're having a hard time believing it works, that's understandable. If you don't want it to be true, you're not alone. | ||
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+ | Here is a quote from one of the buick engineers, in charge of the indy v6 engine program years ago. "We don't agree with Dick's numbers or method, but we still need him to design our camshafts." | ||
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+ | LET ME JUST ADD, THESE FORMULAS ARE THE REAL DEAL. THEY HAVE BEEN PROVEN ACCURATE FOR MANY YEARS. YOU CAN READ MORE ABOUT THE FORMULAS AND THE SOFTWARE THEY RESIDE IN AT www.controlledinduction.com. YOU CAN WATCH A VIDEO OF THE SOFTWARE MODELING AND DESIGNING THE CAMSHAFT FOR A NASCAR CUP ENGINE AT 9000 RPM. | ||
− | + | The software calculates the required valve motion to fill the cylinder and generates the curve, then displays the total calculated cam configuration, as fast as you can enter the values. It is an equation! So, it doesn't matter the engine size. Model a .7854 ci cylinder at 30,000 rpm....not a problem. There is no other software, equation or person, that is more accurate at selecting the right cam. | |
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":[[User:Therightcurve|Therightcurve]] 04:52, 22 August 2015 (MDT) | ":[[User:Therightcurve|Therightcurve]] 04:52, 22 August 2015 (MDT) |