I have followed this thread since the beginning (I can recommend it) and as far as I have understood, MacDonald's car hit the wall with the right rear corner first. It was a very hard blow that tore off the corner and probably also twisted the chassis. I don't know how the fuel lines were placed, but they must have been torn apart and or the fuel tank punctured. In one of the Youtube-films you can see a cloud of fuel round the car just after the first contact with the wall. Maybe someone with more information about fuel system can give more information, but after having read through the whole thread, I don't think there is anything mysterious about this accident. Only sadness....
The fuel tank, a simple rubber bladder (attached to the frame and the bodywork) ruptured.
I have read two different explanations for this to happen, both appear plausible, perhaps even occurrung at the same time.
Since the car had such wide bodywork (full width) and the bodypart was a single piece, once it got in touch with the wall, it instantly `worked on' the unprotected rubber bladder, even despite the fact that the tank was on the opposite direction of the wall and was never in direct contact with the wall.
Another theory has it that the massive fuel load had such an inertia that it sloshed violently through the tank and with such a force that it ruptured the tank. This theory is the one told within the official USAC report on the accident.
Weird as it seems, both theories are indeed plausible enough to explain why the tank leaked after the impact of the car with the wall, despite the fact that the tank was on the opposite side of the cockpit.
I agree with you that there is little chance that it isn't likely that there will be discorverd new facts about the events of that day itself. Perhaps about the aftermath, why such a number of incorrect facts about the cars and their fuel loads were told for so long and accepter as the thruth while a few people who knew and spoke out were ignored.
Good chance that next year, because of the 100th 500 all kind of publications will be released, good chance that 1964 is among the subjects dealt with and will the story about the near 100 gallon cars spilling almost 200 gallons of fuel on the track still be told yet again?
Edited by Henri Greuter, 18 August 2010 - 13:13.