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racingenglishcars
Darth Vader
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Just for kicks I drew up a Matlab m-file with a simplified torque curve and ran it through some calculations to produce the following graphs.
The torque/HP curve is based on some data for a pretty much standard 1100 sprite engine that I found somewhere on the net.
Torque and horsepower
The following shows the torque curve, modified to give the force at the rear wheels pushing the car forward in fourth gear (1:1) with units in Newtons.
It is compared to a curve for wind resistance, rolling resistance and transmission internal friction. I left out some more minor considerations and I only guessed at the last two. Wind resistance is based on Cw=0.43 and frontal area is 1.5 m2.
The point where the two graphs meet is where the forward force equals the drag force, at which time the car won't go any faster. The horizontal axis is MPH.
Four different graphs, each for a differential ratio.
Only minor differences in top speed are seen here, but are a bit more easily seen when I can use the zoom function.
The trend is obvious. The 4.55 tops out in engine speed and the 3.73 rides too far down on the torque curve.
A bit more accurate torque data would be nice, and maybe a better function for rolling resistance.
The torque/HP curve is based on some data for a pretty much standard 1100 sprite engine that I found somewhere on the net.
Torque and horsepower
The following shows the torque curve, modified to give the force at the rear wheels pushing the car forward in fourth gear (1:1) with units in Newtons.
It is compared to a curve for wind resistance, rolling resistance and transmission internal friction. I left out some more minor considerations and I only guessed at the last two. Wind resistance is based on Cw=0.43 and frontal area is 1.5 m2.
The point where the two graphs meet is where the forward force equals the drag force, at which time the car won't go any faster. The horizontal axis is MPH.
Four different graphs, each for a differential ratio.
Only minor differences in top speed are seen here, but are a bit more easily seen when I can use the zoom function.
The trend is obvious. The 4.55 tops out in engine speed and the 3.73 rides too far down on the torque curve.
A bit more accurate torque data would be nice, and maybe a better function for rolling resistance.