4.7 V8 swap?

I don't agree that it's total junk but there are a couple reasons why it's gotten the reputation that it has.

First of all the factories are running the cylinder head temperature higher in order to meet emissions requirements to get at least a 10 year service life out of an engine so that they make their investment back. This requires that the oil change interval be strictly adhered to and high quality oil be used. Synthetic should be used in my opinion and changed at 3000 miles. This will keep the oil from sludging.

Second it's true they can't be bored, and the heads cannot be shaved. If you overheat one it's junk.

Combine these two factors with the fact that they are small, displacement wise, fairly wide for a small motor, and there is very little in the way of performance parts for it and you get an engine that really isn't a desirable swap candidate.