Paul S is right.
The interesting thing to me is how good of mileage european cars used to get in the 1960s.
Getting 30 mpg was average.
With an 948 Austin, 1200 VW, or 800 Fiat, 40 to 45 mpg was possible back then.
I wish we had more cars like them now.
With some fuel injection and other advancements, we should easily be getting over 60 mpg.
But instead we have silly things like automatic transmissions, electric windows, etc., that make modern cars inferior in many way.
If the question is total miles, there is absolutely no limit.
Unless you live in the rustbelt, any car can be driven forever.
The only reason to give up on any car is rust, collision, or vanity.
As for Designer, I completely disagree.
First of all, the old bugs were neither light nor unsafe.
They were always 1800 lbs, because they were originally designed as off road military vehicles.
They constantly found ways to make them lighter, with the 71-75 Super Beetle being the lightest of all.
As for safety, there is not a vehicle safer.
The VW pan far exceeded the safety capability of any other vehicle, because it was much stiffer compared to its weight.
Old VWs have had head on collisions over 50 mph with little passenger harm, because the whole front was a huge shock absorber.
They not only actually got 32 mpg, but if they had actually tried to increase mileage, by lightening design, adding overhead cam, fuel injection, etc., it would not have been hard to double the mileage.
The proof is that in Europe, there are standard VWs that do average over 80 mpg. It is not at all hard to do.
Then there is the claim there are lots of cars currently sold get over 40 mpg, and that is not true. They hybrids are fake because they do not count potential battery costs, and on others the actual mileage is not nearly what they are rated for.
The fact cars now have AC, all power, automatic, electric windows, locks, etc., are what is wrong with them. These are not improvements or things people should actually want on a car. In fact, no rational person should want explosive airbags or ABS that can not stop nearly as fast as any good driver.
additional comment to Designer:
No, the VW was never actually intended for civilian production, and only 2 civilian prototypes were made until the British helped VW retool for civilian production in the 1950s.
The People's car Hitler sold to the German people was totally faked, and he had no intentions of following through on.
And while it is possible for a good driver to get much more than the rated mileage, the reality most get far less.
In fact, I often got over 40 actual mpg with a VW. You said you got 32 mpg with a dual port 1600, so it should not be hard to see an 1100 would get much better mileage than that.
With Fiat 850s, it was not hard to well over 45 mpg.
You missed the whole point. Which is that in Europe NOW, they sell dozens of cars that combine the technology of the 60s with current developments, and rountinely get over 80 mpg. My complaint is that we are not allowed access to these superior mileage cars in this country, and that is criminal. We need to change the DEQ laws to measure total pollution per minute, and not just parts per million. And we need to stop trying to build armored cars that actually are much more deadly.