Does anyone know any specifics on this truck????

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Ricko1966

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I've been trying to get info on this truck for a long time it's 1981/82 and I don't know if any other years it's V8 4 speed it's got to be carbureated. I'm assuming 305,quadrajet and a 833 transmission. But something just doesn't seem right,or there would be lots of people on this forum getting low 20s.
 

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ali_c20

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20 mpg... possible on a flat surface with constant speed. Never ever under real driving conditions. Weight to high and aerodynamics too bad on our bricks.
Now I'm interested too if it was real or just for marketing.
 

GTX63

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Marketing. Those numbers were outliers, and created with setups performed on dynos and test tracks specifically intended for producing the max mpg numbers to satisfy the government and advertising departments. Yes, better than average mileage can be obtained thru better driving and maintenance, or a good tailwind, however, if we all drove like the GM techs did we would have a mass outbreak of road rage.
 

Ricko1966

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My burb got 17 mpg and that wasn't driving particularly nice. Fresh 5.7,mystery cam 700r4 unknown rear gears. My friend Grant who's a gear head doing an L.S. swap right now has always claimed 20+ on his truck. The documentation I posted came from 2 different sources on 2 different year trucks. I think 28 is a stretch,I just wondered if anyone had specifics on this truck,same source lists all the other 82's with figures more like we'd expect 16-20 or so but this one model has unbelievable numbers. I didn't know if someone knew of a special model,different cam,heads,carburetor,advance curve. Etc. Post 1 pic 2 that source has at least 8 or 10 different versions of the 82c with different engines and transmissions,but justv1 with stupid high mpg. Busy right now I'll look it up again later and post more.
 

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TotalyHucked

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I could see 18-20 on a dead flat road (or even slightly downhill) at a steady cruise but nothing else. My 305 got 12mpg no matter what I did, my buddy's 350 fuelie with the 700R4 only managed about 16 and it was bone stock down to the tires.
 

pduffyd

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Im assuming the 305 had an electric carb on it like the M4ME with dancing needles in the primaries. That system worked quiet well it closed loop to get the best MPG with careful driving, I had the same setup in my 84 Monti Carlo SS.
I did transplant a 4L60 into it for the overdrive gear (much like an 833 manual), and got 9Lt/100Km most of the time with a heavy right foot. Once I stuck a crate 350 in it it went to about 11Lt/100 Km. But I thought that was great.
Bit of a different beast though, it didnt have a big flat front like our Squares have for starters.
 

rusted nuts

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I had a 86 1 ton 4x4 dual wheels IO' steel flat bed with 350 Q,jet 4 speed with granny gear,, I think 4;11 gears that would get 15 mph.
 

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Bextreme04

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speed limit on highways was 55mph back then. you'd be amazed at the mpg you can get driving 55mph, even in a brick, compared to cruising at 70-75+ mph today.
Aerodynamic drag is proportional to the square of Velocity. It adds up fast, especially when the coefficient of drag is equivalent to a brick wall.

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SirRobyn0

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If you go to fueleconomy.gov and look up one of our trucks you'll see to estimates for fuel economy. One from back when the vehicle was made and another updated more realistic number.

For what it's worth, my 1984 C20 700R4 3.41 rear end, does about 12MPG on my commute which is a mixture of country roads and city traffic. Before I had the ESC functioning, I did a long highway drive at 55MPH and managed 16MPG, normal highway driving 70-75mph I'd get about 14.5, I just got the ESC fixed the timing and carb dialed in. My last long drive on the highway running 70-75mph I managed 15.6MPG.

A C10 is lighter than a C20 and that C10 may have been equipped with a feedback carburetor. I'm sure those numbers were test numbers and not really world though...
 

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