Not quite on why the speed is strictly limited to 230 MPH: The real reason is that the Speedway can't get insurance if the cars go over 230.
There is also a secondary reason of driver "grey-out" when speeds hit 236 MPH at Texas, which is why the April 29, 2001 CART race was canceled at the last minute when the teams, engine builders (but NOT the chassis builders, who were left out) and Joe Heitzler & his cohorts couldn't reach an agreement on how to slow the cars down.
@Streetrodder: Actually, this year IndyCar switched fuels (again), this time to E85 racing fuel, which is 85% ethanol & 15% Sunoco gas of unknown octane, for an unknown combined octane. For the record, ethanol has an octane rating of 110.
In any event, I miss the smell of methanol while on pit lane :-(
By the way, is your engine builder friend Ed Pink?
I find the article title of Indy Engines Still Pack a 700HP Punch to be deceptive: As Robin Miller pointed out last night on Wind Tunnel, the running joke around The Brickyard is that the Corvette pace car has more horsepower (638 hp) than the race cars (560).
Even with the boost being increased from 130kPa (18.9 psig) to 140kPa (20.3 psig) for qualifying, that's still only a 50-60 hp boost -- And still less than the pace car.
You must be a NASCAR fan. I just read an article the other day on NASCAR and something about Jeff Gordon saying F1 racing was done at the pole position laps and the race was a follow the leader event. I thought this was intresting and I don't watch much racing, but thought F1 race tracks are something totally different from any other racing and the track by nature doesn't allow a lot of passing. 700Hp isn't something to sneeze at. It's quiet a bit of power. Course it's an engine running about 10,000 RPM to produce this power and it's a wonder it doesn't just fly apart.
Actually, unlike NASCAR, IndyCar has had gallon fuel limits for many decades. In fact, Andy Granatelli (of turbine fame) proposed in the late 60's that cars should be allowed any fuel, but only a certain number of total BTU's for the 500 miles.
Where this fell apart in the old days (60's & 70's) is that teams would field a "rabbit" that would burn up more fuel than was needed to complete the race, in the hope of tricking the other racers to run them out of fuel before 500 miles. Remember, we're talking crafty people with names like Foyt, Penske, and Ganassi!
I agree with the sentiment that perhaps the INDY rules should try to include some measure of efficiency, such as limiting fuel tank size to a small volume to impose a minimum MPG threshold (more pit-stops penalize low MPG cars). It all boils down to what focus the race is intended to have.
For example the "Race of Champions" uses identical cars and therefore is all about the drivers. In the 1980's...formula SuperV (SCCA race class) allowed only minor variations in the basic VW engine and heavily specified other variables like tire size - focusing on keeping costs down and of course making driver skill paramount....with only a minor role played by the engine tuners. It was still fun to watch.
Of course, there is the Shell Eco Marathon and the Automotive X-Prize, which focus on efficiency (but nearly eliminate the driver skill aspect and certainly any wheel-to-wheel racing maneuvers). This is mainly about the design of the car and the skill of the tuner. These are also completely boring to watch as spectator sports...therefore useless as a replacement to the spectacle of INDY (or Stock Car or F1) racing.
I would suggest limiting displacement to a 2.0 liter 4 cylinder, which represents an engine that can power 90% of the cars on the road (with turbocharging). As someone who has been a racing enthusiast my entire life - I agree that historically there have been a number of things that have transferred between racing and everyday cars (such as the first turbocharged car in, I recall 1968?). However, engine technology has now gotten so advanced that I'm not sure there still is much transfer. For example, the Formula 1 "KERS" units (Kinetic Energy Recovery Systems) were similar to hybrid technology....but only remotely applicable to real-world cars. Last I heard, the KERS units have been legislated out, because costs were out-of-control, benefits minor, and also added safety risk (high speed flywheels).
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