Might want to watch the videos about the Ford Testing that was done on ONE ENGINE over a period of time. I was involved personally with this ECOBOOST project in Research. The info below is NOT ADVERTISING, it is facts.
Do not think the iron block 6.0 liter engine would be in the same shape as the ecoboost engine personally. Info below.
F-150 EcoBoost Test Engine
A production 3.5L EcoBoost V6 engine, #448AA, was randomly selected from the assembly line at Ford’s Cleveland engine plant. This engine had no idea it was in store for 163k miles of brutal endurance testing.
#448AA was Shipped to dynamometer cell 36B in Ford’s Dearborn, MI engine lab and run for 300 hours, this engine’s first experience was a rapid simulation of 150,000 customer miles, including thermal-shock runs in which the engine was cooled to -20F and then heated to +235F, repeatedly.
The engine was shipped to Ford’s Kansas City truck plant where it was installed in an F-150 4X4 Super-Crew. After assembly the truck was driven to Nygaard Timber in Astoria, Oregon, where it dragged a total of 110,000 pounds of logs across the ground (requiring all 420 ft-lb TQ)
Next they drove the truck to Miami Speedway, and hooked it up to a 2-car open trailer carrying two NASCAR Ford Fusions (a total of 11,300 pounds) and run continuously around the oval track for 24 hours (average speed: 82 mph, distance covered: 1,607 miles)
After this they took the truck to Davis Dam in Arizona, where it beat out the 5.3-liter Chevy Silverado V-8 AND the Ram 5.7-liter Hemi V-8 each pulling 9,000 pounds up a 6 percent grade in an uphill towing contest.
The 3.5-liter twin-turbo EcoBoost engine was removed and then installed in a 7,100-pound F-150 Baja race truck. After 1,200 miles of practice they raced the truck 1060 miles in the SCORE Baja 1000, the toughest off-road race in North America, finishing 1st overall in the Stock Engine class.
The truck’s owner said the engine’s fuel economy was so good compared with his previous V8 he skipped 2 planned fuel stops during the grueling trip from Ensenada to La Paz.
After winning in Baja they sent the engine back to dynamometer cell 36B and dyno-tested one final time. It generated 364HP and 420ft-lb TQ, only one horsepower less than its HP rating and exactly Ford’s given torque rating.
Lastly, for the final episode of the F-150 EcoBoost torture test, Ford Motor Co did a complete engine tear-down and inspection of engine #448AA (never been serviced or previously inspected) in front of thousands at the 2011 North American International Auto Show in Detroit, Michigan.
The engine parts were laid out on three huge tables so that when the tear-down was complete, the engineers and the audience could take a closer look.
https://www.full-race.com/articles/what-is-ecoboost/
Tom V.
ps Everyone is allowed an OPINION. ONE FACT IS WORTH 10,000 OPINIONS.
FACT: The engine was designed to win Le Mans, a 24 hr endurance race. Doing the stuff above was a piece of cake.