Which Fuel And Carburetor Cleaner Additive Brand Wins?
A head-to-head test of 2 fuel and carburetor cleaner additive options with the measured results for each. See how they ranked and watch the full test video.
AMSOIL PI (Performance Improver)
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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 | Combustion chamber cleaning | Carburetor bowl cleaning | Compression test |
|---|---|---|---|
| 1AMSOIL PI (Performance Improver) | used together with AMSOIL Power Foam as what the narrator calls a powerful one-two punch inside the combustion chamber; this result reflects the combined use of both products, not PI in isolation | the narrator states the Performance Improver did not seem to get all the varnish cleaned up inside the carburetor bowl | per the meta chapters only, not narrated aloud in the available transcript: 96 PSI before treatment, 100 PSI after treatment with both AMSOIL products, a 4 PSI increase; this result reflects the combined use of both products, not PI in isolation |
| 2AMSOIL Power Foam | used together with AMSOIL PI as what the narrator calls a powerful one-two punch inside the combustion chamber; this result reflects the combined use of both products, not Power Foam in isolation | not tested | per the meta chapters only, not narrated aloud in the available transcript: 96 PSI before treatment, 100 PSI after treatment with both AMSOIL products, a 4 PSI increase; this result reflects the combined use of both products, not Power Foam in isolation |
How it was tested
- carburetor bowl and combustion chamber deposit/varnish cleaning, visually inspected
- compression test before and after treatment (per meta chapters only)
- engine load test using the mower's engine brake with a see-through fuel tank to observe fuel consumption and smoke
Data notes and caveats
Despite the video's title and description framing this as AMSOIL versus Seafoam and Marvel Mystery Oil, the transcript only actually applies and tests AMSOIL Power Foam and AMSOIL PI in this video; Seafoam and Marvel Mystery Oil are referenced only as products tested in separate prior videos, and a meta chapter titled 'Same process used to test Seafoam and Marvel Mystery Oil' confirms this refers to the same test PROCEDURE being reused across videos, not that those two products are retested here. Because of this, isHeadToHead is false and there is no winner, runnerUp, or budgetPick in this file; treat data/re-pull or a cross-reference to the separate Seafoam/MMO videos as the way to build an actual comparison, not this single video. The narrator ends the video by asking viewers whether they think AMSOIL is as good as Seafoam and Marvel Mystery Oil rather than declaring a verdict himself. The compression test figures (96 PSI before, 100 PSI after) and the smoke/engine-brake observations come only from meta chapter titles, not from narrated speech in the available transcript, and reflect the combined effect of using both AMSOIL products together, not either product in isolation.
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