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OK, I'm not one who is obsessed with fuel mileage, but every time I get a new vehicle I try to get a baseline, just to know what to expect from it. So Sunday I get up and run over to the Shell station and fill up the Vette, I decide to take a cruise, no destination in mind.
I end up driving all over southern Arizona, all on two lane highways (no interstates), so then Monday and now today I drove all over town. As I was coming home I looked at the fuel gauge and it was just above 1/4 tank so I pull in and fill it up (15.4 gal.), I then look at the trip meter (298 miles), that 19.35 MPG. WOW!!
Is anyone else getting this good of mileage? I don't remember any of my other C3s getting this kind of mileage. Although I think the 700R4 w/ lock-up converter has a lot to do w/ it.
A friend has a 73 with a zz4 motor and had a turbo 400 in it with 3.08 gears and he could average 15 with it. Put in a bowtie 700 trans and it jumped to 21.
I dream of breaking double digits. Some say that it may have something to do with my lead foot. I wonder what they mean by that...
When I first started thinking of getting a C3 as a DD my wife asked "what kind of mileage do you think you'll get?" I told her anything above 10 MPG is a bonus, because that's where I thought it would be (10-12).
2025 C3 ('68-'73) of the Year Finalist - Unmodified
2024 C3 of the Year Finalist - Unmodified
2023 C3 of the Year Finalist - Unmodified
5-7 mpg around town 9-10 hwy. Must use super 93 & 2 cans of boost. Cost me almost $75.00 to fill up Cost to drive in fuel only is almost $1.00 per mile. Around town it's fill up every hundred miles or so, i feel like i live at the gas station !!!
Ho Hummmm, I guess thats The Price you pay for a BB W / 3 Carbs
5-7 mpg around town 9-10 hwy. Must use super 93 & 2 cans of boost. Cost me almost $75.00 to fill up Cost to drive in fuel only is almost $1.00 per mile. Around town it's fill up every hundred miles or so, i feel like i live at the gas station !!!
Ho Hummmm, I guess thats The Price you pay for a BB W / 3 Carbs
Yea, but driving a car that nice is worth every penny...
Best highway tank for my '78 350ci 4spd manual was 18.43mpg.
The average is 16.26 mixed driving.
The worst was 14.19 (excessive use of the loud pedal)
These figures were before the TPI conversion.
I can get in the 24 mpg range with my 700r4, but even with the th350 it wasn't really that bad. Remember, 81-82 vettes will have a 2.87 or even higher rear end in it. They're built for gas mileage (at least as much as was possible back then).
OK, I'm not one who is obsessed with fuel mileage, but every time I get a new vehicle I try to get a baseline, just to know what to expect from it. So Sunday I get up and run over to the Shell station and fill up the Vette, I decide to take a cruise, no destination in mind.
I end up driving all over southern Arizona, all on two lane highways (no interstates), so then Monday and now today I drove all over town. As I was coming home I looked at the fuel gauge and it was just above 1/4 tank so I pull in and fill it up (15.4 gal.), I then look at the trip meter (298 miles), that 19.35 MPG. WOW!!
Is anyone else getting this good of mileage? I don't remember any of my other C3s getting this kind of mileage. Although I think the 700R4 w/ lock-up converter has a lot to do w/ it.
I topped-off the tank of my box-stock '82 (Cross-Fire, 700-R4, 2.87:1 gears ), then drove from near Pixburgh to Altoona, Pa. (over the Allegheny Mountains ) and back (2-lane roads to / Interstate Highways back ), a 236-mile round trip (A/C on with T-tops off during the return trip ), in just under 10 gallons of gas:
after swapping to 3.73s, I made similar trip (A/C on ), this time to Huntingdon, Pa. and back, followed by around-town driving, getting 17.6 MPG over 440 miles of driving.
I have a mostly stock 76 L48 w/3 speed auto that is my DD(20 mis each way). Depending on traffic through the week, I get 13-15 on average in town, around 18 on trips.
When the motor was stock, I was getting 17.9 mpg on trips. 14mpg in town.
Now...With dual exhaust, edelbrock performer intake, edelbrock 600cfm carb & slight cam 14 mpg on trips. 12-13 in town.
You would think with the newer/more modern efficient intake system & less restrictive exhauset that the MPG would have gotten better....Or that was my wishful thinking
When the motor was stock, I was getting 17.9 mpg on trips. 14mpg in town.
Now...With dual exhaust, edelbrock performer intake, edelbrock 600cfm carb & slight cam 14 mpg on trips. 12-13 in town.
You would think with the newer/more modern efficient intake system & less restrictive exhauset that the MPG would have gotten better....Or that was my wishful thinking
When brand-new/stock, my '79 Z28 got 10-city/14-highway.....
tore-out the cat & installed dual straight-pipes, .450"/220* cam, 650 double-pump Holley, headers, intake, etc., got 14-city/18-highway, while ET/MPH went from 16-flat @ 82 to 14.40 @ 97.
When I ran a 350/350 with slant plug heads, Torker Intake, 600 Holley DP, and water injection to stop detonation (11:1 CR) , I typically got 16 mpg on the highway with a peak of 20 mpg.
With my built 355 (Comp Cams 294S, 2.055" intake Aluminum Brodix -8 Pro Heads, Victor Jr Intake, 10.67:1 CR, 750 Holley DP) I get 11 to 12 mpg on the interstate.