I've finally got my new 302 (from my previous thread about low vacuum) running pretty well with the Pony Carbs Spreadbore on there, but my fuel mileage on my 50 mile round trip today was pretty abysmal...I'd say around 10 MPG. Plug #1 is black, #5 had dark spots but was dark gray, as was #8. Anyone know what these carbs run for jets? I'm guessing I'll have to back down at least 2 sizes and check the float level. On the other hand, it's running nicely, and idling pretty well. Anyone else running one of these things?