I agree completely with QuietOne. I have one on my 86 Vert. Have less than $1000 invested in the whole set up with all the upgrades done. They are a great entry level supercharger and work great if kept under 8 psi and not daily driven or used in extreme cold. So I would say if you are selling the complete set up and it has very low miles and use since it was upgraded then in the 800-1100 range. If it had been more than 6 months or 3000 miles since it was upgrades than closer to the 800 range. If your just selling the head unit, then 400-600. Beings it's a Ford Motorsport one it is more desirable to some people. The BD-10 is the smaller unit so that is a down side. The BD-11a is the more desirable out of the BD series. And the X-1a is the highest boost capable of the Powerdynes but they didn't make many and they did have some issues with bearing failure. Hope this helps.
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