removing exhaust restrictions (cats) will do more to improve performance than tinkering with the fuel mixture. You might try Nitrous Oxide injection or a supercharger too, but that might just blow the engine up. As another poster pointed out, fuel and air have to mix in the proper proportions to burn best...adding more fuel will not result in more power unless it is mixed with more air.

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Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz