I agree with Irv......a wise man........except that Irv let his mechanic open up the engine for no reason other than curiosity it will probably go the heck. Why would we do anything other than IAV maintenance recommendation.....it's the guide and is tested......well being tested. I like the idea of Genuine Elio Parts too.Like most of you I have seen the arguments over the proper oil to use, the best filter, and oil change intervals. Internet "experts" are all over the map on this subject. I recommend that you not worry about it and use the oil and change intervals recommended by Elio, when they are published.
If you don't like old Volvos you may never have heard of Irv Gordon. I like old Volvos (I have three of them.) I got to meet Irv in 2010 at a Volvo meet in Kansas. His car has a CB radio, driving lights and a row of mileage badges from Volvo. Other than that it is just as it was the day he bought it. Except it has A LOT of miles on it.
At around 600,000 miles he let his mechanic take the head off to inspect the engine. This was more to appease the mechanic's curiosity than anything else; he had never seen an engine with over 600,000 miles on it. He could not find even a ridge in the top of the cylinders!
There have been repairs, of course. Some body work. Some interior work. Normal wear items have been replaced on schedule. But the car has the original engine, transmission, and rear end.
Irv is now well past 3 million miles on his 1966 Volvo P1800. Every mile he puts on the car is a new record for a privately owned, non-commercial vehicle. He has been asked time and again, "What is the secret to making a car last for three million miles?" Irv's response:
"Just follow the owner's manual. It's a piece of machinery and can't take care of itself. Have its scheduled maintenance completed. … Do what the manual calls for, not what the dealer calls for. People who built the car wrote the manual.
"Use gasoline from a high-volume station to keep crud out of your engine. It's also good to wash your car regularly and wax at least twice a year.
"When your car makes a funny noise, listen to it. Use only genuine Volvo parts for repairs."
Irv is 75 now. He was asked, after the 3 million mile day, if he thought 4 million miles is possible. "There is no doubt the car can do it. I don't know about me though."