Tips on Changing Power
more in the car racing tips series

Tailoring engine power to meet you needs is simple if you know what engine performance parts to change.  These car racing tips apply to all engine performance parts regardless if you have a Ford Mustang, Chevy Camaro, Corvette, hot rods or roadster.  So use these horsepower tips to pick the right engine performance parts to fit your needs.

Whether you are using the basic Engine Shop software or all the way up to Engine Analyzer Pro, software programs can calculate the changes in power for changes to your specific engine parts combination.


Move curve up & down

When you review your engine's power curve and you feel that the power curve is too low on the graph, there are specific performance parts that can be changed in the engine that will move the whole power curve up or down on the graph.

Engine items that effect the thermal efficiency (see Engine Science 1) tend to move the whole power curve up or down on the graph. One easy way to move the curve up on the graph is to increase the engine's compression ratio.


Move curve
left & right

If you feel the need to move your engine's peak torque to a higher or lower RPM, try changing the cam, header lengths or the intake manifold runner lengths. Changing these performance parts in your engine may move the peak slightly higher or lower on the graph, but the major movement "rocks" the curve and moves the peak to the left or right on the graph.


Right tail
of curve

If your engine's torque curve falls off sharply as seen in the illustration above, then this is an indication that your engine can't breathe well enough. This problem is typical of small carburetors, small valves, and divided intake manifold plenumns. I t can also be caused by a low mechanical efficiency (see Engine Science).

Using your engine software, you will notice that changing engine performance parts to improve the right side of the torque curve will also increase the peak horsepower and change the RPM of the peak horsepower.

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