Sheehan - QV with improved different pistons and rings?

I like this quote = If you’re clever, your neighbors will refer to you as “the guy up the street who must have won the lottery because he’s driving a Ferrari.” If you’re not, they’ll remember you as “the guy who used to live up the street but ended up selling his house because his Ferrari needed a new engine.”

 

KS Pistons ( Kolbenschmidt) are very good

 

There certainly was a change as Mondial 8, 308 carb and 308i-2V use a piston with 4 piston rings and Mondial QV and 308QV use a piston with 3 piston rings. What confuses this issue is that some early 2Vi engines had some sort of ring seating problem so used a lot of oil, and led F to develop the ridiculous warranty specification that "if it uses less than 1 quart of oil in 600 miles (1000 Km), it's OK, and we are not replacing the engine for free" . F still uses this specification on many models that followed, but no engine in decent condition uses this much oil. Later design is always better, but no one is taking a good-running 2-Valve and is in a panic to replace the pistons. There is some risk that an early 2Vi engine might have an oil consumption problem if never fixed, but, if it's had regular use, any problem in this area should have already surfaced:

308 carb: Special Cast Iron Liners, 4-ring pistons
early Mondial 8, 308i-2V: Special Cast Iron Liners, 4-ring pistons (some risk about excessive oil use and many had engine replacements)
later Mondial 8, 308i-2V: Special Cast Iron Liners, 4-ring pistons (they did some fix)
Mondial QV, 308QV: Aluminum Alloy Liners with Nikasil coating, 3-ring pistons

But QV do get a price premium for this and other issues.