Which Fuel And Oil Additive Brand Wins?
This head-to-head test of 2 fuel and oil additive options has the measured results for each. See how they ranked and watch the full test video.
Some figures on this page were transcribed from the test video and have not been independently re-verified. Treat the numbers as a close guide and watch the full video for the exact readings.
Marvel Mystery Oil
Price shown in test: $3.50 for 32 oz
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The measured results
Every number below is read straight from the test. Products are listed in the order they finished.
All measurements (3 more)+
Application method
- 1Marvel Mystery Oil
added via a bag-and-clamp setup to control flow rate into the carburetor, 8 oz added to match the amount used with SeaFoam in a prior video, followed by a hot soak of the engine with additional Marvel Mystery Oil for at least 20 minutes with the spark plug removed
- 2SeaFoamnot tested
Cold compression test
- 1Marvel Mystery Oil
a video chapter title reads '106 PSI cold,' but the transcript's spoken narration does not state this figure or confirm which product it belongs to; kept as an unconfirmed, chapter-only data point
- 2SeaFoamnot tested
Prior video results referenced
- 2SeaFoam
described as having done a phenomenal job improving engine compression and removing carbon deposits from the combustion chamber
- 1Marvel Mystery Oilnot tested
How it was tested
- cold engine compression test
- warm engine compression test
- hot soak treatment of the engine with the additive
- carbon deposit removal (referenced from a prior SeaFoam video, not retested here)
