Ferrocene octane booster

[Testarossa]

Ferrocene is an iron compound used to replace tetraethyl lead. It's the active ingredient in Lucas octane booster. On the way home from Telluride a couple of weeks ago I got a bad tank of gas and had a little pinging, so I poured a few ounces of the Lucas stuff into the tank. It cured the pinging. I ran the tank down a couple of gallons and refilled with good 91 octane. Had a nice fast run over to Cedaredge on Sunday including a full-throttle blast up a short but steep hill.

Pulled the plugs today and was surprised to see a rust-colored deposit on all the steel surfaces except the center electrode. Turns out this is common with ferrocene additives. It's "normal" except that the iron deposit is conductive so eventually the buildup could reduce impedence between the electrodes. So I'll run out this tank and replace the plugs.

Anyone else have experience with this stuff?

[Rough Edge racing]

 Another opinion on the rust color from another racer friend 

that orange color is characteristic of methyl tertiary butyl ether. it used to be a common octane booster in pump fuel and also in parts store bottles. it makes it hard to read the plug.

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