I've never seen a Trabant with this sort of modification done to it. Either someone has tried it and there is a reason behind it, or nobody has thought of it which I find hard to believe. Years ago I threw a V-belt on my Fiat 124 Spider. The weirdest thing. The belt had stretched (probably from removing it more than a few times), flipped itself inside out yet was still wrapped around all three pulleys! But it was stretched to the point there was too much slack to tighten it. Luckily I was not far from an autoparts store. Ever since then I keep a spare V-belt with me in most of the old cars. The first thing I noticed was a sudden increase in power. Then I noticed the battery indicator light was on and the temperature gauge was starting to rise. My guess is because due to the lack of drag on the alternator and water pump explained the increase in power. This always made me wonder if it were possible to install an electro-magnetic clutch either on the crankshaft pulley or water pump or alternator that would disengage whenever the turbo kicked in to reduce engine drag. Since the turbo is only spinning in a few second bursts, I could possibly get away without over heating or discharging the battery. I could even add an over ride switch if I wanted to. Well I never got around to it on the Fiat but about a year ago, about the same thing happened again but with my Trabant. I did not get the "tit" on the fan housing aligned with the hole in the engine cradle and eventually I threw a belt. If you ever throw a V-belt on a Trabant, you will definitely know it. The engine RPMs will dramatically increase. Kind of like if the throttle return spring breaks. Which has also happened to me. I don't know how much drag the mechanical fan or alternator creates on a Trabant so I don't know if this would be a worthwhile experiment. Mounting the fan could be easy with some custom brackets but the question is the mechanical fan spins in proportion to the engine speed. Anyone ever notice that when pulling away from a redlight after sitting for about a minute, there is this sudden burst of heat from the heater? Unless some sort of speed controller was used to regulate the fan, it would spin the same no matter what the engine was turning. I don't know what effect this would have. The other concern is engine temperature. It may run either too hot or too cold. The engine temperature would need to be monitored with the mechanical fan then compared using the electric fan to make sure the temperature stays within range. If the electric fan could not adequately cool the engine at full throttle, I guess a shroud and duct could be installed to channel air through the front grill.