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Originally Posted by Andrew@ActiveAutowerke
A car acceleration for 30+ mph before hand has a clear advantage.
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Why?
The acceleration is the rate of change in velocity, and rate of change of velocity will be the determined by the sum of all forces. On one hand, you have the motor output giving a +force (influenced by air density, etc.). Other forces include road friction, wind resistance, slope, vehicle mass, rotating mass,etc. Momentum is just mass × velocity and is not a force acting on the car. Assuming you can keep everything constant except engine output,then the car under free acceleration shouldn't have anymore advantage than the other car which only started to accelerate 10-20 KPH sooner and is under same boost levels.I'm not a physics guy, but this is the way I understand it.
Maybe one of the physics guys could chime in and explain if I'm right or wrong.
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Our driver did say a car came in his lane at the end there(high beam flash) and he let off for a sec which is why it stopped accelerating for a second at the end there
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Too hard to tell if he let off cuz of the radio playing in the background. Ask your guy if he can re-do the run from very slow to top speed again. Would be nice to see if it makes a difference. And of course if he has a vBox, then we have a program that will recreate the race like this:
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Vbox or a good old fashion rolling race is the the only trustworthy way.
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Agreed.
BTW, I've actually done 60-130 vbox testing with rolling starts vs. "hitting the gas" @ ~50MPH. I wanted to see if the rolling start was faster or not than just punching it. I did the tests all on the same night and all on the same road with the same car. I've
got to admit that my best 60-130 was from a rolling start, but it was by less than 1/10th of a second (0.010) -- which on a 6MT is no real difference at all. I have it all on video vbox so its easy to post and verify the results if requested.
Assuming both cars have the same mass, on the same road road at same day/time,they effectively accelerate the same.