2 bbl or 4?

[86SILVERADO]

I have a 350 from a 76 suburban that I just put in my 67 C30 I can't decide if I should use the 2 jet setup or the quadrajet. I have the 1 3/8 venturi 2 bbl rated at 435 cfm which is plenty for my 350. I only have an emissions era quadrajet which I know I can get to work with a few modifications. I am mainly concerned with what will give me the best gas milage since I don't need massive power due to the sm420 trans and 4.10 rear end. Anyone with experience with the difference in economy between a 2 jet and quadrajet?

[Don Smith]

I've run them both. Currently running a quadrajet. I am getting slightly better fuel milage and much better driveability with the quadrajet.

[dinnut]

run the quadrajet. i got 2 trucks. one with the 4 and one with the 2. the 4 is so much better.

[Tx Firefighter]

I'll buy those 2bbl carbs from you guys who don't like them.

[dinnut]

really tx? ill be getting rid of the one i have on my 72 probably...
intake too. when i put my 4bbl intake and carb off my 70l... interested? its a replacement 2bbl built by holley they base cracked after about a week of use (pos plastic or something) and so we went to a junkyard found the correct carbeuretor dissasembled them and used the base plate off the steel junkyard carb on the holley...
i could sell it to you. i also have the rest of the junkyard carb sitting in my garage if interested...

[Tx Firefighter]

I love 2 bbl carbs. I use them for other things. I like them because I can usually pick them up for 5 or 10 bucks.

They are the Rodney Dangerfield of carbs. They get no respect.

[dinnut]

hmm interested in buying them tx?

[Tx Firefighter]

how much $?

and let's see some pictures..........

[jewels.]

this is interesting.... i am faced with this same decision.... my 2bbl carb is in need of being rebuilt, and i chose to stick with it over the 4bbl to keep better gas mileage and because of the price....

the 2bbl carb i have only cost me a few bucks, and a rebuild kit on it is about $20 (including the float).... so its pretty cheap to purchase and maintain....

my brother (a mechanic) told me that i would get better gas mileage with the 4bbl if i can keep my foot off the pedal (and thus out of the secondaries)....

but another mechanic told me that the two carbs are realistically the same when it comes to gas mileage because they both run two primaries most of the time.... he said that the way a carberator is adjusted affects the gas mileage more than whether or not it is a 2bbl or a 4bbl.....

does this make sense? comments anyone?

thanks!
jewels.

[Longhorn Man]

If you are talking quadra-jet, or edelbrock, then you'll probably get better MPG (keeping your foot out of it).
If you flip one of them over, you'll see the primaries are real small, all the CFM is in the secondaries.