Seems hard to believe the additives could really make that much of a difference. The fuel itself is generally the same among the brands. Only the additives change, and even then only a few brands have their own branded additive. Shell is one of them, chevron is another.
There are several YouTube videos actually using Shell and Chevron as well as other top brands on the dyno. Shell and Chevron always come out on top.
Seems hard to believe the additives could really make that much of a difference. The fuel itself is generally the same among the brands. Only the additives change, and even then only a few brands have their own branded additive. Shell is one of them, chevron is another.