Engine Fuel Aug 2019 Test: Which Brand Wins?
In our Aug 2019 test we compared 2 engine fuel options head to head. Unleaded gasoline came out on top. See the measured results, the runner-up, the budget pick, and a link to the full test video.
Unleaded gasoline
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The quick take
The short version of why each pick lands where it does, built straight from the measured results.
“Now, I definitely don't recommend using aviation fuel in your car just because it's going to cause problems for the catalytic converter and probably the sensors as well.”
The measured results
Every number below is read straight from the test. Products are listed in the order they finished.
All measurements (6 more)+
Lead buildup and combustion chamber inspection
- 1Unleaded gasoline
used as the clean baseline, combustion chamber cleaned before switching to aviation fuel, no lead deposits reported
- 2100LL Avgas 100 octane low lead aviation fuelnot tested
Lead buildup on spark plug and combustion chamber, small engine
- 2100LL Avgas 100 octane low lead aviation fuel
spark plug showed a much lighter color than typical from visible lead, clumps of lead build up found near the spark plug, intake valve, and exhaust valve inside the cylinder head
- 1Unleaded gasolinenot tested
Predator 212 running characteristics
- 2100LL Avgas 100 octane low lead aviation fuel
engine initially ran very rich to the point it would not idle until the air fuel ratio was adjusted leaner, after which it ran a lot better; target was to beat a baseline top speed of 29 mph but the resulting top speed on avgas is not stated in the transcript
- 1Unleaded gasolinenot tested
Fuel injected generator under load
- 2100LL Avgas 100 octane low lead aviation fuel
tested under an applied load per the video chapters, over 4,000 watts, outcome not detailed in the transcript
- 1Unleaded gasolinenot tested
Wankel rotary engine, see through cover
- 2100LL Avgas 100 octane low lead aviation fuel
engine ran successfully on the aviation fuel, host called it really cool to see it run on avgas
- 1Unleaded gasolinenot tested
Go kart engine
- 2100LL Avgas 100 octane low lead aviation fuel
ran too rich on aviation fuel and had to be leaned out
- 1Unleaded gasolinenot tested
How it was tested
- visual lead buildup inspection on spark plug and combustion chamber
- compression test
- running characteristics and top speed test in a Predator 212 engine
- load test in a fuel injected generator
- running a Wankel rotary engine with a see through cover
- flame color comparison in a see through cylinder head engine
“Now, I definitely don't recommend using aviation fuel in your car just because it's going to cause problems for the catalytic converter and probably the sensors as well.”
More Fuel & Additives
Which Fuel Stabilizer (plus A Separate 1-year Headlight Restoration Kit Durability Check-in) Brand Wins?
Sta-Bil
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Which Diesel Anti Gel Fuel Additive Brand Wins?
Hot Shot's Secret
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Which Gasoline Octane Grade Brand Wins?
87 Octane
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