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Old 10-12-2011, 12:48 PM   #23 (permalink)
itjstagame
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Join Date: Sep 2008
Location: Thomaston, CT
Posts: 23

Commuter Plus - '98 Saturn SW2
Last 3: 37.12 mpg (US)

Rover - '07 Land Rover LR3 HSE
Last 3: 17.6 mpg (US)

Blackie - '16 Ford Focus Titanium Hatchback
90 day: 33.25 mpg (US)

Bertha - '11 Four Winds Chateau 31a
90 day: 7.79 mpg (US)

Van - '15 Honda Odyssey EX
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Quote:
Originally Posted by mwebb View Post

consider a carburated system from the 70s and a 2012 any car from now ....
same mass ,
FE is better by a huge percentage and emissions are greatly reduced on the
current systems compared to the 70s cars
While I agree this is true for american made cars there are exceptions and the 70s is a bad time frame to pick because of the gas crisis there were a LOT of very FE cars in the 70s. Additionally carbs and TBI were not that different FE wise in the 80s, we really only saw improvements with injectors and tuning improvements heading in to the 90s. Carbs actually vaporize fuel and I believe overall required less maintenance, injectors are just cheaper and easier to tune now.




I know this is the 80s, but I think it's worth noting this is 52MPG from a carb while GM was busy throwing a TBI on everything and still getting worse FE.

Anyway I agree with you overall, just wanted to point out that carbs could be quite amazing and while cars produce less pollution per unit of exhaust volume, I do not believe overall we're getting that much less pollution per mile.

Actually if you want to really go back you should look at when they first removed lead from fuel, only in the past 15-20 years have we really reclaimed that lost HP and FE from having to severally lower our compression ratios and tune for a cat that wouldn't really be necessary with the correctly build engine or tune.
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