If you have a mechanical fuel pump, than you will need the eccentric. If your car uses a type of fuel injection, there will not be a need for the eccentric.
i do not believe they do due to the fact the 86's were injected. the 85's would though. the 86's also don't have notched pistons which a lot of aftermarket heads need.
Well I'm building the motor right now, and I found what looks like an eccentric in my parts. The notch and hole in the center would fit perfectly on the cam drive sprocket. Looks like the timing cover is large enough for it to fit. I know I don't need it, but was wondering if anyone with an 86 block knew if it has one installedfrom the factory for whatever reason.
Being a transition year motor you never know. I owned an 86 and have an 85 so I think I have good experience with these since I ended up installing the 86 motor in the 85 using the carbed setup. It could be a left over from 85 or it could have received an 85 engine at some point. Also, it could be the oil slinger and you are mistaking if for an eccentric. In 85, Ford used a 2 piece eccentric instead of the crappier and heavier 1 piece setup. Im willing to bet the timing chain cover has a boss for the mechanical fuel pump, but no hole??