Burgundymog, yes engines run fine without air filters, they just don't last as long. If you are going to keep the car it's much cheaper to fit a good air filter than to keep rebuilding the engine!!
YMMV.
Cheers
John.
Well, 61 years,122,000 miles and 1 engine rebuild (96,000 miles) seems to have lasted quite long without using air filters. Maybe I will fit an air filter and it can go to 250,000 miles without another engine rebuild!!!