Tom Del Rosso wrote:
> This always bugged me. Why is firing order always non-consecutive?
>
>

It's simple. it's not possible to balance the crankshaft in most engines
to do that and still have an engine that fit's into a vehicle. Take a
simple 4 cylinder. The crank throws have to be 90 degrees off from each
other to maintain balance. Then you need to balance out the rocking
coupled frequency from the firing order. If you don't the vibration will
quickly destroy the engine.

On a V engine you have 2 cylinders on each crank throw. So you have
cylinders 1&2, 3&4, 5&6 each sharing a throw. Number one is at TDC but
number two is already past TDC and heading down the bore by the time
number one fires. Impossible to have them fire in sequence.

There are some engines out there that have a sequential firing order,
but the crankshafts have split journals and generally they are not
capable of much power output because of the crank design.


--
Steve W.