How long does it take gas to lose its octane.

 

If it's in a sealed drum a long long time. We gas that was over a year old at the last NMRA reace that we did and it passed tech just fine. But if it's just in the ground or in your tank I bet a few months is all it lasts at most.

 

After thirty days in a gas tank I would be suspicious.A sealed container should be able to keep it good forever.

 

My car has sat for two months and it starts realy rough. The gas in the tank is probably done huh

 

You can save the gas you have in the tank by filling up with new,fresh gas.My bikes go through this sometimes when the weather is bad and topping off the tank helps a lot.It doesn't take much.

 

As JD said, it will keep for some time if it is sealed. One thing you have to watch out for is condensation while gas is being stored. If the container isn't full, temperature changes can cause condensation inside the container, and dilute down the gas. Keep containers full, while in storage, especially in areas prone to temp change.