Time to switch to a Rochester Quadrajet?

[chriswalkoe]

I just did a 55 mile round trip drive, all freeway, and I filled up before leaving and right when I got back.  13.75 mpg.  Ug 

My truck is my daily driver so I need to maximize my gas mileage.  Would it make sense to switch over to a quadrajet?  My motor is a Gen 1 350 Chevy with headers, dual exhaust and mild cam (I have no idea what the specs are).  Cast iron intake.  4 speed manual, 31x10.5 tires and stock rear end as far as I can tell.  82' K10.

Any advice would be appreciated!

[chriswalkoe]

I forgot to add I have an Edelbrock Performer carb on their now.  Not sure of the size

[rockable]

Do you have a 1405 (manual choke) or 1406 (electric choke)?  The 1405 is designed and jetted for aggressive engines.  The 1406 will get better mileage and work better with a mild cam.

[chriswalkoe]

When I got the truck it was rigged to be manual even though it might be electric.  In any event, there is no juice running to the choke and I removed the manual setup which was rigged wrong anyway.  The truck seems to run fine which is why I haven't addressed it yet

[rockable]

The problem is not the choke.  It is the calibration of the carburetor.  I.e. different jets, centuries, bleed jets, etc.  I changed mine out on my hot rod and got much better mileage and adjustability.  I put a 1403 on my truck.  I am sure it will do fine once adjusted and set up properly,  it is a 500 Cfm version.

[bake74]

I just did a 55 mile round trip drive, all freeway, and I filled up before leaving and right when I got back.  13.75 mpg.  Ug 

My truck is my daily driver so I need to maximize my gas mileage.  Would it make sense to switch over to a quadrajet?  My motor is a Gen 1 350 Chevy with headers, dual exhaust and mild cam (I have no idea what the specs are).  Cast iron intake.  4 speed manual, 31x10.5 tires and stock rear end as far as I can tell.  82' K10.

Any advice would be appreciated!

     With your current set up, I would say you are getting pretty good mileage, considering no overdrive and a standard transmission.  I know you want more and as rockable said it would make a small difference in carb's, but only to the point of you keeping your foot out of the secondaries.
     Have to ask, does it have a good tune up ?  Tires inflated correctly ?  All these little things can make up 1 or 1.5 mpg with the proper driving technique's.
     Other than that your taking about TBI or FI for your engine, or overdrive for your transmission.  Or rear end swap to a taller set so you get better hyway mileage.
     I assume it is 2wd since you did not mention 4wd.

[chriswalkoe]

Tires are inflated to 40 psi and the motor has new wires and plugs and a clean air filter.  I have yet to have the carb checked out or the distributor.  It seems to run fine though, idles well, and has enough power considering it's stock with a cam (not sure what it is, just a nice lope to it).  The truck is a 4wd K10 with a NP204

[werewolfx13]

Sure its not an np203 or 205? I've never heard of one of these trucks with anything but a 203, 205, or 208...

[Jason S]

I think getting 13.75 mpg on the highway out of a 1982 Chevrolet K10 with a carburetor and no overdrive is doing pretty well.  I get 14 mpg on the highway out of my 2005 Chevrolet 2500 4x4 with fuel injection and 5-speed overdrive manual transmission.

You could probably do some tuning and change metering rods on the Edelbrock you have and gain a little extra mpg, but I wouldn't expect to gain a whole lot of extra mpg. Without knowing all the details (especially axle gear ratio) the highway mpg doesn't sound horrible considering your setup. 

The Quadrajet can give you a crisper throttle response, but the difference between a properly tuned Q-jet versus a properly tuned AFB/Edelbrock should be minimal. A newer design intake and heads may give you some more power and possibly a bit more mpg, but probably isn't worth the investment if you're primarily concerned with fuel mileage.

[Andyman]

Hello, I'm new on the forum here, and looking around at posts that contain "quadrajet," and came across this. Admittingly, I don't know much about the specific equipment mentioned here, but I do know that 2 bbl carbs get much better mileage than 4's. Also, sometimes the secondaries on a 4bbl can be disconnected and that results in better mileage too. Just thought I'd mention that since nobody else did.

[csdineley]

13.75 mpg isn't that bad my 87 tbi 350, 3/4 ton, 2wd can squeeze out 14 on the highway if I'm really trying.