pamotorman wrote: ↑Tue Apr 02, 2019 9:43 am
back in the flat head ford days 180 degree cranks were used to fire 2 cylinders at one time for more torque
This racing legend has been around since the Winfield Model T days,
a Model T engine has only two intake ports. By making a crank shaft that has two in front aligned and two in the rear aligned, it makes the engine a four port and so lets you have one fire. then three, then two and then four. Any firing order can be used but the efficiency is improved by evening out the power pulses rather than one two, four, three. That system makes you get the front two in line while the back ones do nothing. The air must first go twice to the front and then twice to the rear as if it was controlled by traffic lights. The two up two down is more efficient because it alternates the firing into equal distribution. Ed Winfield also tuned the intake manifold runners so that the air pulses did not overlap or interfere with one another. it allows the efficient use of a much more "aggressive" camshaft ( much longer duration
but it's still wrong. The best version of it I ever heard was, "But the flat crank won't work in a Chevy; stroke is too short. That long stroke makes the torque."
As Mike says, any advantage of the flat crank has always been better intake and exhaust tuning. If there is more torque produced, better breathing is the cause; not the stroke or the firing order.
