There are many more 740s on the road than 760s and 780s. -and amid the 760s, you are more likely to find Turbo-4 engines than PRV-6 engines (amid the brickboard regulars). The B230 engines are definately easier to maintain than the B280s (and the B28s) and that probably contributes to the number that are still on the road 15 years after production.

Either way, I do have a B280 in my '88 780 and I have no serious complaints about it. -she purs like a kitten and I keep up the service schedule and do preventative maintance on it.

When posting here on the brickboard, I'll do my best to answer your questions. There are several others who are as equally or more knowledgeable about the PRV-6, but not all of us have the time to read every post. Sorry we can't be omnipresent, but we'll do our best to read regularly and post what we can answer.

God bless,
Fitz Fitzgerald.
--
'87 Blue 240 Wagon, 244k miles.