How many mpg do u get?
12-17-06, 03:41 PM
#51
Old [Sch|F]ool
Originally Posted by aws140
. also, all the specs on your drivetrain please. i know you have the 4.78, stock wheels/tires, 207(?)m stock engine, and FC tranny. what carb? thanks.
5th gear with the FC trans and 4.78 is just like 5th gear with an early FB trans and 3.91. So, imagine making 1-4 a whole bunch shorter then a huge gap to 5th. SUCKS. Gets rid of much of the advantage of using the 4.78 - bringing the closer 3-4-5 spread down to speeds where they are more useable. With the FC trans, there is no nice 3-4-5 spread.
The 4.78 probably makes for worse fuel economy than the 3.91 because of higher internal friction. I have never run the 4.78 without synthetic oil, and I never ran the 3.91 with synthetic, so I have no idea there.
You also have to know how to drive, too. Maintain momentum and all that.
04-06-07, 08:10 AM
#57
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I daily drive a street ported 12A with Weber 48IDA, very short trips so the engine is barely warmed up by the time I get to work. When taking off from stop lights, I will NOT be out run if the motor is warmed up and I can help it 
Taking my driving style, the short trips with cold street ported motor into count, I get 16 mpg in the city. When I get out on the highway and the motor is warm for a long trip, then the mileage goes up to 24 mpg - a 50% improvement over 16 mpg.
Taking my driving style, the short trips with cold street ported motor into count, I get 16 mpg in the city. When I get out on the highway and the motor is warm for a long trip, then the mileage goes up to 24 mpg - a 50% improvement over 16 mpg.
04-06-07, 10:23 AM
#61
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1984 GS, all stock except the heater flap has been removed from the air cleaner and a Purolator FPR set to 2.5 psi has been installed...19 - 21 mpg depending on 85 or 75 mph drive to work during the week.
04-16-08, 01:41 PM
#74
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Good info here.
I was searching for MPG and came up with this thread.
So lets get it going again
I am considering an FB or FC as a commuter, so this is part of my pre-purchase research
I was searching for MPG and came up with this thread.
So lets get it going again
I am considering an FB or FC as a commuter, so this is part of my pre-purchase research
04-16-08, 01:55 PM
#75
djessence
rx7doctor had an interesting thread about increasing mpg. I think he gets like 30+ now. I believe its in the non tech. probably still on the first page.
Ill see if i can find it for you. In general rx7's arent great on fuel, ESPECIALLY for the size of engine lol
Ill see if i can find it for you. In general rx7's arent great on fuel, ESPECIALLY for the size of engine lol