Has anyone ever come across a device that would convert the M sync of your average pack film Polaroid to X sync? It doesn't seem like it would be so hard to make something that adds a 20 ms delay so that an electronic flash would fire at the right time, but Google came up with nothing.
That is basically a work around - bump up the power on the flash to get a longer duration - and so far has been a bit too much trial and lots of error for my liking. I've also got a 360 which has its own dedicated flash but I'll need to get a 240/110 stepdown transformer (for the charger) and replace the nicads in the flash before I even know whether it will work. Other options all involve some sort of hacking which is why I am looking for a plug-in solution before I reach for the Dremel.
You can build a delay circuit, I suppose, or perhaps purchase one pre made. I am sure you could learn how to do it with a visit to the library.
If you like to shoot tons of Polaroids, I would look at Mamiya Universals as well. They are great cameras, and they are pretty light with the Polaroid back (not so much with a film back).
The easiest (but probably not the best) method would be to use the camera's contacts to operate a relay and use the relay's switch contacts to fire the flash. This will probably not introduce enough delay by itself but to increase the delay, I would use something like a 5 volt relay with a 9 volt battery and have a series resistor in line which is similar in value to the resistance of the relay's coil. I would then experiment with connecting capacitors across the coil to delay the turn on time.