Comments by "earthstick" (@earthstick) on "Driver61" channel.

  1.  @danspeed7039  I think they must be the same length otherwise gases from early firing cylinders that travel through longer pipes will arrive at the junction at the same time as gases from later firing cylinders that travel through shorter pipes. The aim is to reduce the gases passing through the junction at any given moment.
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  2. Those primary pipes, is the aim to have them the same length? Because the cylinders fire at different times the exhaust gases will begin their journey at different times. If the pipes are the same length then the gases from each cylinder will take the same amount of time to arrive at the junction and remain out of sync with each other thereby reducing the gas passing through the junction at any one moment.
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