The Fuel Hierarchy | K&M Performance

The Fuel Treatment Hierarchy

BEYOND BRAND LOYALTY: WHAT ACTUALLY TOUCHES MY ENGINES

The K&M Performance Standard

As an AMSOIL dealer, I stand by their lubricants 100%. But when it comes to what goes into my fuel tanks—whether it's my Harleys, my racecar, or my personal trucks—I have a strict hierarchy based on decades of testing and mechanical reality. There are only four products that touch any engine I own. Period.

1. Berryman B-12 Chemtool

When you need high-solvency "bite" to dissolve varnish and carbon deposits that modern detergents won't touch, Berryman B-12 is the nuclear option. It’s a machinist’s staple for a reason: it works on the heavy-duty scale where others fall short.

2. Seafoam Motor Treatment

The gold standard for moisture management and cleaning in small engines and fuel systems that sit. It’s a versatile tool for keeping internal passages clear and preventing the "gumming" that kills performance in precision-machined components.

3. Marvel Mystery Oil (MMO)

This is my secret weapon for top-end lubrication. I add an ounce or two to every single tank on my Harleys and my racecar. It provides a layer of lubrication for the valves and upper cylinders that prevents dry-start scouring and keeps the mechanicals moving smoothly under high-heat conditions.

4. AMSOIL Fuel Treatments

While I reach for the others first for specific cleaning and top-end tasks, AMSOIL treatments are excellent for modern injectors and overall fuel system health. I use and sell them because they are engineered to the same high standards as their oil, providing a clean-burning, modern solution for daily drivers and fleets.

Why It Matters

At K&M Performance, we don't just sell what's on the shelf; we sell what works in the real world. Whether you are managing the high-lift cams of a race engine or the delicate tolerances of a V-Twin, choosing the right fuel additive is about matching the chemical to the mechanical requirement.