I need somebody to double check my work I think my math is wrong somewhere

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The discussion focuses on verifying the calculations in a spreadsheet designed to convert vehicle data into a horsepower chart, resembling a street dyno. The user reports that their calculated horsepower is approximately 25% higher than the expected value of 447 horsepower and 396 torque. There is a mention of including a dyno correction factor for SAE values, but confusion arises regarding the units used for torque and angular speed. The importance of using consistent units, such as foot-pounds for torque and radians per second for angular speed, is emphasized to ensure accurate calculations. The user seeks assistance to identify and correct the discrepancies in their math.
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I need somebody to double check my work...I think my math is wrong somewhere..

so I've been working on a spreadsheet to take some data from a vehicle's data port...
and to transfer it into a Horsepower chart...
basically making a street Dyno...

I've gotten everything to work together...including graphing
but I know that my math has to be wrong somewhere and I need some help to get it right...

I think I've done all the conversions correctly...
I know I've done all the lookup from my data page correctly...

The Data I used is from a vehcile on the dyno...this vehicle made 447HorsePower and 396 Torque
but my excel math seems to say it s a lot higher...a lot higher..my end result is 25% or so higher than what it should be...
I've even added in dyno correction factor that every dynomometer uses to get an SAE corrected valueMy link to my excel spreadsheet...in a zip file...
too big for me to post it...
http://www.audiohelix.com/physics/
 
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In a consistent system of units we have:

Power = Torque * (rotational speed)

You stated that your are measuring power in units of horsepower (instead of, for example, watts).

When you say 396 Torque, you are ommiting the units. The most likely possibility in America is foot-lbs, whereas with the metric system torque is measured in Newton-meters.

The metric unit for angular speed is radians per second (not revolutions per second, as engines are often quoted). To convert revolutions per second to radians per second multiply by 2*pi = 6.28.
 

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