David,

You are right. I do "Love" this Volvo and that is the problem. This was the first Volvo my wife and I purchased new shortly after we got married. My youngest daughter, age 21 currently drives it at college in VA. I let her take it because I knew none of her friends would borrow it because it was a manual. There is another issue: the piston rings are worn. When you accelerate from a stop, blue smoke can be seen from the exhaust. It goes away once the engine hits cruising speed. My mechanic said it would make sense to address that issue at the same time the valves are fixed, but it would be additional money. Meanwhile since I posted the query above, I have located a used motor out of a 1997 850 with just under 52,000 miles that can be shipped to CT for $1,100. I don't know how much the cost to install it would be. I would bother too the car no longer had the original engine, but installing a used one may be the way to go. Of course, dumping even that kind of money into a 25 year old Volvo with 430,000 miles, doesn't make sense economically.

Thank you for sharing your thoughts about 91 vs 87 octane. I hope I make the right decision. We don't last forever, and neither do Volvos. But still....

Hugh