General rule of thumb, i'd say 100 miles in a car = 1 engine hour on a boat. But like any rule of thumb, it's not applicable to everything, and in most cases, it really doesn't mean anything. my old mans boat has 1800 hours on the 454's, but it's a cruiser. 180,000 miles equivalent and still going strong, by my rule of thumb.
Take a supercharged big block engine in about the only automotive application where you'd find that nowadays - drag racing - and your 112 hours is the same as 11,200 miles. Figuring half of that in the car would be 1/4 mile at a time, that's not too far off. Although I do agree that a failure at 112 hours is unacceptable for a 525. For a 1075, that might be acceptable.
Put a blower on your car engine, the life will shorten dramatically. Run your boat around N/A, and spend 95% of the time under 3500 rpm, and it'll life a long happy life.