How much Sea Foam in fuel (max) [SOLVED]

Hi Josie. You can add a lot of Sea Foam to fuel.  For example, mechanics with fuel rail cleaning adapter machines use 50% Sea Foam mixed with gasoline. For your question, the most you should add would be around 50 ounces, so three 16 ounce cans would be a good rule.  Even though you can add a lot of Sea Foam, you need enough light ignition vapor in gasoline to be volatile enough to run easily in the engine. I hope this makes sense!