| Message | of gas in the tank when the reserve light comes on, then I recommended adding 5 more gallons on top.  In the "Octane Olympics" article on my website, 30% was considered the maximum. The 2:5 ratio you mentioned is 40%, assuming that toluene mixes with gas in a linear fashion, which it does not, but close enough for our purposes. Running too much toluene is not inherently dangerous. Toluene is harder to ignite than gasoline and running higher concentrations will lead to poor cold starting and eventually rough running, but the engine will not "blow up" if the toluene percentage is too high. Can't comment about the soot, never noticed any more than my usual.  
 
 
 "Straight-line acceleration is probably the first aspect of automotive performance that any intelligent driver gets bored with." Peter Gregg
 "We owe a lot to the dragsters. They always break something, figure out a way to beef up the part and the benefit trickles down." Robo
 "Not everything that can be counted counts.  Not everything that counts can be counted." Einstein
 "And now my friend, the first-a rule of Italian driving,  [Franco rips off his rear-view mirror and throws it out of the car] what's-a behind me is not important."  Raul Julia, playing Franco Bertollini while driving a Ferrari Daytona in the movie Gumball Rally
 
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