Hmm. Pure oxygen, atmospheric pressure, iron and heat equals
Thermal lance.
It would allow lean burn without nitrous oxide, but the unused oxygen would be a risk for the engine.
If you reduce the pressure to near-vacuum then it could work, but you'd have massive pumping loss. And you will have to store the oxygen at very low temperature or very high pressure, turning your car into a potentially explosive device.
It is pressure, not heat, that makes your engine work. 80% of the air entering is inert, but will raise in volume when heated up. Without it the mixture would need to be 5 times as hot to provide the same pressure.
Even with air as it is there are heat issues, that's why
water injection, adding inert matter to trade heat for volume, can be effective.
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2011 Honda Insight + HID, LEDs, tiny PV panel, extra brake pad return springs, neutral wheel alignment, 44/42 PSI (air), PHEV light (inop), tightened wheel nut.
lifetime FE over 0.2 Gigameter or 0.13 Megamile.
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