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47 Fasttoys · 02-08-2014, 03:06 AM

20 MPG on an AD series would be a stretch, the problem is that parachute in front of the hood. Add that to the wide tires and increased roll resistance you you have when running them and even with the best gearing and carb. you would be lucky to get 18. Then I had my '54 I ran a 350/700R4, 273 gear in the rear end and a 600 Holley. With 235/75/15 the best I could do was 18. Now I normally run 70 on the highway. If I would back to 65 it might help a little, but 2 MPH, no so sure.
Rob

02-08-2014, 03:06 AM	#8
47 Fasttoys Registered User Join Date: Sep 2013 Location: Westminster, SC Posts: 933	Re: Carbruator for best gas mileage 20 MPG on an AD series would be a stretch, the problem is that parachute in front of the hood. Add that to the wide tires and increased roll resistance you you have when running them and even with the best gearing and carb. you would be lucky to get 18. Then I had my '54 I ran a 350/700R4, 273 gear in the rear end and a 600 Holley. With 235/75/15 the best I could do was 18. Now I normally run 70 on the highway. If I would back to 65 it might help a little, but 2 MPH, no so sure. Rob __________________ My '47 C.O.E build