As long as you are using the Talstar P at the proper dilution rate in the tank, the metering rate would just be dependent on how quickly you are walking during application. Unfortunatley, we do not carry Stihl blowers so we cannot give you an exact answer. However, we can thell you that with our Solo 451 blower, we suggest a metereing rate of 2 (from a range of 1-4) for a normal pace during application. For most applications, you will mix 0.5-1 oz per gallon per 1,000 sq ft.
Unfortunately, Talstar P is not labeled to treat for fruit flies. Getting rid of fruit flies doesn't have to be diffucult. The most important step is to be sure that you discard or refrigerate any ripe produce as insects are naturally drawn to overripe, rotting, and spoled produce. Regularly rinse out and clean gargabe cans and recycling bins. Most times doing these small little things will take care of the problem. However, should you need to use a product to help you get rid of them one of the best ways to kill fruit flies is to use a fuit fly trap like the Vector 960 Furit Fly Trap. These have attractants in them that attract the fruit flies to them, and once they are inside they cannot get out. You can also use an aerosol product to help with the populations as well like 565 Plus XLO.