How were the engine fuel options tested?

Each option was put through: 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.

Where can I watch the full test?

The complete hands-on test video is on the original creator's channel: https://www.youtube.com/watch?v=D7_rpEejTKk

2019 test2 productsFuel & Additives

Which Engine Fuel Brand Wins?

Q: Which engine fuel brand wins?

Unleaded gasoline came out on top in a head-to-head test of 2 options. The verdict: "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."

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.

The verdict

Winner

Unleaded gasoline

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The measured results

Every number below is read straight from the test. Scroll sideways to see all measurements. Products are listed in the order they finished.

Product	Lead buildup and combustion chamber inspection	Lead buildup on spark plug and combustion chamber, small engine	Predator 212 running characteristics	Fuel injected generator under load	Wankel rotary engine, see through cover	Go kart engine
1Unleaded gasoline	used as the clean baseline, combustion chamber cleaned before switching to aviation fuel, no lead deposits reported	not tested	not tested	not tested	not tested	not tested
2100LL Avgas 100 octane low lead aviation fuel	not tested	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	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	tested under an applied load per the video chapters, over 4,000 watts, outcome not detailed in the transcript	engine ran successfully on the aviation fuel, host called it really cool to see it run on avgas	ran too rich on aviation fuel and had to be leaned out

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.”
From the test video verdict.

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