Cheap Gas in a Cheap Car

So you have 240,000 miles on your 1986 Volvo 740. You've used cheap gas the whole time you've owned it so you don't see any reason to use any better gas at this point in time, do you? Probably not, most owners wouldn't spend much money on any car that is worth less than a thousand dollars. Heck, most wont even vacuum it. But will cheap gas in an old bomber like that make matters worse?
Lets look at synthetic oil for example. I have heard people say that if you have a high mileage engine, using synthetic oil could make an old engine run better and last longer, but I have also heard that it is useless to use unless you started using it when the car was new. So, if cheap gas prices mean you can find some discount gas to put in your old car, should you use it?
As I have stated in other posts, there is conflicting evidence that there is any such thing as cheap gas from a quality perspective. Some groups will tell you that gas is gas and it's a waste of money buying more expensive fuels. Others people will say that certain gas stations carry premium fuel. If you decide to buy more expensive fuel that is your choice, but should you?
Well, if your cheap car is running poorly and has certain conditions, like spark knock, cheap gas can be a cause of that. You may want to try running a mid-grade or premium fuel a couple times to see if makes any difference. You could also look into buying a fuel additive to see if that helps with engine performance.

Where's The Cheap Gas At?