On Google
Check out www.v8buick.com. There you will find all the info you need for your engine.
You don't calculate the firing order. You simply follow the manufactures firing order for your engine. Click the link and you will find the firing order.
Firing order is 1-3-4-2.
You need to look for the firing order for your specific engine. That's the order you place the plug wires in. Make sure the rotation of the distributor matches the firing order.
First find out what the firing order of the engine is. Then locate the #1 spark plug. Once you find that and know the firing order and the direction the rotor turns you can easily connect the spark plug wires correctly. Ask your question again with this term. "Firing order and spark plug diagram of (list make, model, & engine size)".
If you look on the intake manifold of any engine you will find the firing order.
find out what engine is in it, and look online for a diagram, honestly thats the safest way to go.
The firing order diagram for this car is found in its owners manual. It is also found in the maintenance and repair manual book as well.
Try 1-8-4-3-6-5-7-2 CLOCKWISE The firing order is above. If you need a diagram you can get one at http://www.classiccarauto.com/impala/how_to/firing_order.shtml .
Google it
Click the link.