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-   -   New Carb Results (https://67-72chevytrucks.com/vboard/showthread.php?t=17644)

Mike C 07-06-2002 07:04 PM

New Carb Results
 
Well, after a month long wait, I got my Jet Stage II 750 Q-jet from Summit. The first tank of gas around town netted 10.1 mpg, driving in my normal full throttle up to speed methods. (FYI, internal combustion engines operate at max efficiency WOT and it takes a certain number of BTU to do the work, and by burning them more efficiently, you get better mileage than babying it! Try to maintain a constant speed and stay 65 or below. Think about it...) Tank 2 was this weekend. Went from Austin to Goldthwaite, drove around a little the 3 days we were there, then headed back this am. Results of tank 2, 12.8 mpg! I'm quite pleased with that. My truck has the original 402 with 2 1/2" dual exhaust, a 270 Crower cam and open element air filter. It has 3.54 gears with 30.5" tall tires (265 75 16) and a TH400. I drove 65 the whole way. Speed limit was 70, but wind noise goes up exponentially and my AC crapped out earlier this summer. I'm still toying with swapping in the SM465 as I think it would net an automatic 15% increase in fuel economy on the road. I wouldn't have figured the auto trans and 400 ci would let it get above 11. I was averaging about 8 in town and 10 on the road with the original carb, so I consider it money well spent but I did have to fab a bracket to use my mechanical linkage as the carb came with a cable type setup. Talking with my neighbor, he has managed to get 13.1 out of his 2002 6.0 3.4 ton truck. So I figure his .3 mpg cost him over 30k bucks!!!! And I guarantee nobody at the pump goes' "cool truck, man."

Longhorn Man 07-06-2002 08:01 PM

12...not too bad. Esp for a pig block. ;)


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