I am looking at a couple of 66 Galaxie 500s, one a 390 and the other a 7 litre. The latter is supposed to be a 427. Is there a simple way to distinguish between the 427 and 428 visually? Popping the hoods on both cars the engines look identical, again one reportedly a 427 the other a 390. Both cars appear to be in original condition

 

No simple way. measure the stroke. All FE blocks are basically the same,
of course the 427 side oiler has that oil galley running down the side..
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was the side oiler used in passenger cars in 1966? I am still trying to determine the value of these cars, and if the 7 Litre is in fact a 427 there is a significant bump in value. Not many of these cars came with the 427 as they switched to the 428 mid year.

 

Like anything going back that far, It's hard to say. I would not say it was a stock
engine in any Ford, but it might have been an special order if you knew someone.
Like you said, they started using the 428 which came out in 66, the 427 ended
in 67... 428 with it's longer stroke\more torque for street use.
It's interesting that people say that all the FE were the same block and they basically
were, but then so was the "Y Block" and the 385 series 460\429 . When you get to
the Windsor blocks there is a difference starting with 221 going to a 351w.
1965-1972 Ford Car Engine Identification Tag Codes - FORDification.com
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