318 MAX fuel economy builds?

gagembassett said

So I'm looking into buying a long-distance capable daily driver. I have my eyes on a Dodge Diplomat and Chrysler 5th Avenue. Both have 318s and I thought it may be of my own interest to buy one as a daily as they are things I can work on instead of things I would need to take to a shop. In the case that I buy one or the other I would like to build the 318 for high fuel economy, I'm talking like 20+ mpg if possible. Anyone done this? Any input? Etc. Let's coffee-table talk daily stuff instead of high horsepower for once.

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Should be doable without all the "theory". Main thing will be the carb, exhaust and ignition. Assuming both have a 2.45 rear, the first is a a good ignition. I run Taylor Spiro Core wires, platinum spark plugs, new cap, and new rotor. Convert to Chrysler electronic if you have any ignition problems. Play with timing to run as much advanced as the engine will allow. The best carbs for mpg are the 73?-75? BBD Carter with the adjustable rod hanger, Thermo-Quad, and the Quadra-Jet (318 and 360 trucks and vans). We could get 25 mpg with a factory 75 Cordoba 318 BBD and have gotten the same or better with the Thermo-quad. A good Quadra-Jet should be close to the Thermo-Quad. Use a Performance or Vacuum gage.