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Discussion Starter · #1 ·
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?
 

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Discussion Starter · #2 ·
I found that it had 55 primary jets in there, despite having a 1" primary venturi setup! I put a set of 48Fs in there, and it's already cleaning the plugs up after 15 miles. A guy on another board that has one of these said he thought his primary jets were 42 or 44s. Yikes was that thing rich. I have a set of 44s on order. The secondary jets are 62s, which seems about right for 1.12 secondaries. My 1.08 junker has 57s on the secondaries.
 

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BTW, my owner's manual lists the jet sizes for each engine option...The "Open Crankcase System" has far larger secondary jets than the "Closed System..." What did Ford consider open and closed? Judging by what the car originally had for jets (it's been in the family since '68), it seems like it's a closed system, but it has nothing connecting the oil cap breather to the air cleaner.
 

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My guess is closed has a PCV valve and line to the carb, open would be a draft tube. Don't look at the oil filler cap, look at the other valve cover and see if there is a PCV valve and line running up to the carb.
 
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