Very small amounts of Propylene Oxide was / is added to Glo fuel to improve ignition. This was especially common when very high nitro percentages are used just to get the stuff to ignite consistently. Too much P. O. and you get pre-ignition and erratic running. It is a great aid for starting Glo engines in cold weather. Its evaporation rate is similar to ether though so containers must be tightly capped. Staying on subject, this or something similar might be the secret ignition improver as it has a very low flash point.