|Questions and Answers on Ferrocene|
[We're dealing with model racing airplanes. (In case a search engine brought you here.)]
Check my article if you haven't already.
Wingeter used the Ferrocene in heat of Brazilian Championship and he thought his engine was more potent too, but he thinks the product is abrasive and appeared risks in piston.
It's a correct observation that ferrocene gives iron oxides as a product from combustion, and red iron oxide is the same as the "jeweler's rouge" abrasive. Increased wear is reported for cars, and this is the reason it hasn't been used there.
I tested ferrocene for a few months before I told anyone, and then a few more teams used it for more than a year before I published my results. Wear of pistons hasn't been a problem for me, and no other team has reported they think that the wear has increased in comparison to TEL based fuel. There is probably more iron oxide on the piston to cylinder mating surface than on the piston pin fit. Still the piston pin seat is where the the worst wear occurs. For me the piston pins come loose and are replaced by .01 mm larger ones while reaming the hole a few times over before the pistons get too loose in the cylinder.
It should be remembered that there is lots of aluminum dust in the engine from all wear on the aluminum parts. This soon turns into aluminum oxide, which is a very hard abrasive. This means that there is a strong reason to clean the engine carefully after each day's running in any case. This takes care of any problems with iron oxides too.
Literature on the subject says that ferrocene could be combined with an organic copper compund to reduce wear, as a mixture of copper and iron oxide is much softer. I haven't found any reason to try this yet.