Dyno numbers....

so spank me with your key board.. The program needs a frontal area figure entered in order to calculate the drag of the vehicle being tested. With out it the results show more power than what is really being made. Time is also a key figure in the program, the more time it takes to go from point A to point B the less power the vehicle is making.
 
Time is a key factor in horsepower calculation.
The reason is actually super simple: 1hp = 550 ft.lbs/second. In other words, 1 horsepower by definition can "lift" a 550 pound weight 1 foot in 1 second. (or a 1 pound weight 550 feet)

550 pounds per second... so in one minute, that's 33,000 pounds (60 seconds in a minute). And of course 1hp will also lift ONE pound 33,000' in one minute... you can change feet and pounds all you want as long as the number comes out to 550 pound-feet (for a second of work) or 33,000 pound-feet (for a minute of work). Since we think in terms of "RPM" (rotations per MINUTE) on our engines, we stick with 33,000 pound-feet per minute.
 
Not really interested in figure, want test an engine, change something and then retest the engine to see if i have made an improvement. is there anyway to do this
 
A few ways of doing that. Simplest for a home build would be a big brake that can dissipate some heat and a lever arm on a scale. Load it up at your desired rpm and read the scale. Or use an oil pump to get the load. Inertia is simpler to use but you would need some software to time the run, or be really good with a stopwatch. Decide first if you want to do sweep runs or single/step load points.
 
You are expecting too large of gains for these engines. We can build, tune and test an engine to gain .5 lb/ft of torque in a small RPM range, thismay give you a 1-2 tenths of a second in one sector of the track, and we are happy. That gain is not felt in the seat of the pants, it requires an average of several Dyno runs, and many consistent laps accurately timed. Many simply state he I rev my engine to 8250 and I want another 200 RPM what gear do I run. That makes me think of the Civics that drive by down town, 6000 RPM in 1st gear making all kinds of noise but no go just noise.
 
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