If I drink 8 tall boys of an evening what time in the orning will I be able to drive?

One alcohol unit is measured as 10ml of pure alcohol. This equals one 25ml single measure of whisky (ABV 40%), or a third of a pint of beer (ABV 5-6%) or half a standard (175ml) glass of red wine (ABV 12%)

The average human liver process approximately 1 unit of alcohol per hour. This means that if you drink 12 units, it'll take you roughly 12 hours to fully sober up.

For your "tall boy", you need to work out how many units are in your cans (beers in cans come in different strengths), this will be written on the outside of the can.

Realistically you should wait until you have metabolised ALL the alcohol before you drive.