5 cylinder firing order

[hunker7]

I am doing my 3rd year project on 5 cylinder engine, and just got curious on firing order . I've read that it's not recommended to have combustion in the cylinders that are side by side as that causes force to become one sided? AAN fires 1-2-4-5-3, why would Audi choose to fire 1-2 and 4-5 instead of 1-3-5-4-2 which would fire only one "pair" of cylinders?

Hope it makes sense

[kymi]

In your example there's 5-4 and 2-1 pairs. So I see no difference.

[hunker7]

In your example there's 5-4 and 2-1 pairs. So I see no difference.

Completely missed that Been doing some reading since I posted, and it seems that 1-2-4-5-3 results in much smoother running engine than 1-3-5-4-2.

[kymi]

1-3-5-4-2, what's the next cylinder firing? 1-3-5-4-2 -> 1-3-5-4-2. Basically it's just reversed AAN firing order.