One guy on the 'Port posted this (obviously a recreational pilot):
I burn Shell V-90 in "da liddle birdie" because it is no-lead and (in Ontario, at least for the moment) un-polluted with corn juice. I can't recall anything smelling unusual, for either the "da liddle birdie" or "da heap" (2000 Neon with approaching 300,000 km on the cheapest gut-rot gas available), but I don't normally go around smelling gas pump nozzles. Sounds kinda weird, doncha know?
The Franklin engine is only 7:1 compression ratio (in 1947, the standard gas was 72 octane, and no lead), so 100LL is merely an expensive and annoyingly effective source of lead-fouled spark plugs. I have noticed that the plugs stay much cleaner since I abandoned avgas (and six cylinders times two plugs each times $60 - $70 a plug (14mm plugs are decidedly non-standard in the aviation world), PLUS shipping/taxes/excise adds up real fast.....).
Is the improved plug performance caused by the absence of tetra-ethyl lead? Or is there something to the nitrogen content claim Shell makes? I'm not a chemist, so I can't say, and I can't/don't want to experiment, because I have precisely zero other no-ethanol choices, but I would note that nitrogen isn't quite as inert as has previously been suggested. Chemical munitions are largely based on nitrogen compounds for a reason.
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