Junior tuned the Evo today...

I had a tiny bit on the outside of the stockers, but when I took the blue giants out that I ran for 2+ years they had NONE. The gunk itself is part of an additive in the fuel, there was a gentleman that did a lab test and found that he could recreate it by boiling the fuel until the residue is left behind. The chemical structure was identical to “black goo” but it was clear.