I find mine gets a lot more pops and bangs with 99 over 95, it also idles better with the cams, and I get better mpg, I try to use it once every month for a tank as said above it helps clean the engine, I also use it for trackdays as the car seems to get a lower sound reading on it...
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Red Escort 1.6LX
Then - Red Escort 1.4
Then - Silver Fiesta ST 170BHP
Then - White Fiesta ST MR200+
Now - Mitsubishi Evo IV Forged 2.3 500BHP
and Mondeo Mk3 2.0TDCI