What is the spark plug gap 1.4 astra?

Depending on the year of the car, and (for later models at least) whether it is 8 or 16 valve, the gap is either 30-thou (0.7mm) or 40-thou (0.8mm) If your car has 2 or 4-electrode spark plugs, it is usual for these to be replaced if the gap is excessively large.