Auto Parts: ford carb spacer, fe engine, block engines

Question
I have a water cooled carb spacer (4 barrel) off a 65 390 fe engine...I understand it will not work on small block engines,why?

Answer
    There is no reason why it could not be used on any engine, providing the bolt pattern matches up.  Ford didn't use these for long, I think because they mostly didn't work very well.  In the summer, this is going to turn into a carb heater, and might very well promote vapor lock or worse.  I honestly think that a phenolic insulator/spacer, in concert with a heat shield (less important, and sometimes hard to fit), is the best answer to any sort of carb heat problem.  Also, if you buy a good quality spacer, like Wilson, you will improve performance by a significant margin.  Raising the carb up an inch or two always improves performance, if you've got room under the hood.  The first inch is more important than the second (or so she says).