[ConservativeMind]

Yo-Yo is right. You can find a list of gas stations with much higher detergents by visiting TopTierGas.com. Each brand has certified that all octanes and all gas stations with that brand have the same very high detergent additives, as their minimum (highest octanes could have even more, but all are much better than other companies' fuels).

http://www.toptiergas.com/

[PAR35]

A bit off topic, but I stopped into a Kroger gas station to get some cheap gas. I found out that the reason it was cheap is that you had to pay separately for the detergents - a flat fee per fillup instead of per-gallon. I figured one tank without detergents wouldn’t clog the injectors, but I made sure I got the next tank somewhere else, and I haven’t been back.