The Offy was a high stung engine that required a lot of frequent adjustement to keep running right. It was a "mechanical marvel" indeed. But computer controlled fuel injected engines ran a bit better for a lot longer with less work required. Also, I think that the newer engines were a bit cheaper.
There is not enough down-force for the IndyCar drivers to be pedal-to-the-metal around the turns at Indianapolis. The drivers must lift and negotiate the turn...or be in the wall! Even with the new safer barriers around the turns, it's still a very hard hit when into the wall. If the car does not handle well, all that power won't help the driver stay up to speed.
The fuel cell (tanks) are much smaller than yesteryear for safety sake. A smaller fuel supply means more pit stops.
IndyCar has chosen to go with smaller displacement engines, this year allowing turbochargers with a slightly smaller displacement. Cost containment is a major factor, and there is a cost limit to how much the teams will be charged for each engine...the same for the chassis.
As for "big bore" American racing...that's NASCAR.
I can see where the headline is confusing, Dan. As you seem to know already, the top level of horsepower for a car in the Indy race series is different than that of the Indy 500 because of permissable boost levels. The Indy 500 is 550-560 HP; the Indy car series is about 700 HP. We put 700 HP in the headline because it's the top output. Sorry for the confusion.
As for durability, I believe the new rule for IndyCar engines is that the engines must last 1,850 miles. The Chevrolet cars all started last for the Long Beach Gran Prix due to an engine change for all the Chevy's. Will Power still won driving a Chevrolet.
Watching people drive remote controlled cars (robot cars) would be as boring as watching people play video games.
There is no replacement for big racing (sporting) names like Andretti, Foyt, Unser and Fittipaldi. Race fans generally have their favorite driver, as well as their favorite brand of car/engine. Big-name sports stars provide the performance and fill the stands.
For those not interested in professional sports, including auto racing, don't watch and don't attend. To each thier own.
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