The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - What kind of gas mileage do you get with your 67-72?

Blue GMC · 08-16-2020, 12:14 PM

When I was running the original 292, 2 barrel with the 4 speed and 4:10s 15 no matter what I did driving it.

Pulled that out and put in a 350 bored 60 over Vortec heads mild cam, 600 cfm carb, TH350 stage 2 shift kit and 2500 stall with the same 4:10 rear. Lucky to get 6 intown. I think I have a problem as the last time I had her on the highway went from Wichita to Eureka, KS 67 mile trip one way drained the whole tank at 60 mph and almost pulled over to get the spare gallon out I had in the bed the needle was so far below E when I hit town.

08-16-2020, 12:14 PM	#65
Blue GMC Registered User Join Date: Jul 2014 Location: Olathe, KS Posts: 384	Re: What kind of gas mileage do you get with your 67-72? When I was running the original 292, 2 barrel with the 4 speed and 4:10s 15 no matter what I did driving it. Pulled that out and put in a 350 bored 60 over Vortec heads mild cam, 600 cfm carb, TH350 stage 2 shift kit and 2500 stall with the same 4:10 rear. Lucky to get 6 intown. I think I have a problem as the last time I had her on the highway went from Wichita to Eureka, KS 67 mile trip one way drained the whole tank at 60 mph and almost pulled over to get the spare gallon out I had in the bed the needle was so far below E when I hit town.