Edelbock 1406 or holley 080457

[454Man]

Both are 600cfm carbs. Since I don't have time to wait on my carb guy, so I will have to get one of these from oriellys. Which one would you guys get if your 350 had 9:5 comp and a comp cams 260 with 212 duration and .44 lift

[1980c10]

I have similar specs to yours and I really like my holley 670sa never tried an edelbrock. A 600cfm would hold my engine back (from dyno testing). It runs great with a 770 but it runs perfect with the 670 with the same size jets as the 770. The theory with using the 670 over the 770 was to prevent vacuum loss.
What ever you do; consider more cfm. Others will advise against it but the dyno is a pretty honest machine.

[454Man]

I too am one for more cfm... simply because every v8 truck and car that came from the factory with a qjet was either a 750 or 800 cfm carb. Now simply because of the choices I'm given at the parts store for sameday purchase I have there two carbs to choose from. However I will lookup the carb you have to see what it cost and shipping time frame will be. By chance do you know the jet/ rod size you used for the 670sa? Or did you just use it as is? Anyone else have their input? Thanks

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[78 Chevyrado]

Bigger CFM carb gives worse throttle reponse off idle.  Smaller CFM carb will lose top end if your engine actually needs it.  Q-jets are the most responsive solely because its a spread bore, no other reason. 

a stock 350 only needs approx 450CFM or less  and thats at around 4500RPM. 

Q-jets are larger yes, but the primaries are super small, and the secondaries will only open just enough to give the engine EXACTLY what it requires air-wise, no matter what you do to it.

If a 350 uses 750CFM, its above 6000RPM and has enormous valves. 

I'd buy a holley if you want tune-ability to get every ounce of power out of it. 
I'd buy edelbrock if you want to tune it once and forget it.  except for weather changes.

[454Man]

Well said. If I had more time id stick with the qjet. Now I'm kinda torn between the edel and the holl. Id like to tune it once and forget about it, but I know a holley has a tuning edge that makes it a little more functional. Everyday driving in mind I may look at the edelbrock. Idk not sure yet.

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[78 Chevyrado]

what RPM is the max your engine will turn?  That's the main thing that determines your CFM.  I like mine in a stock form to be good to 4500RPM.  in a mild build I like it to be good to 5500RPM.  but if you want more, nows the time to set it up for it, carb wise anyway.

[Grim 82]

I've had both and I prefer and use the 600 Holley. If you have a 700r4 or you are very concerned with fuel economy go with the q-jet.

[454Man]

Maybe 4500 to 5000 rpm max. I will still have the qjet rebuilt but mean time I need something now. My trans will also get replaced with a 700r4 little later so ill throw on the qjet and 700 at about the same time. mpgs are a factor but I can't be too picky right now seeing as I'm in a rush

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[TexasRed]

get the summit carb, overnighted it should be cheaper than either the holley or edelbrock.

[1980c10]

Forget about spreadbore squarebore arguments/Holley vs edelbrock vs q-jet as well. Best performance and effiency will be found with a proper air fuel ratio throughout the rpm range period. Mine run perfect with a 770 out of the box (after adding an open spacer to balance the banks) on the dyno with a/f sensors. thats good enough for me. I went with the 670 to keep the vacuum up as I to drive it on the street. I see 17-21 mpg consistantly and dynos at 400 hp. Any carb can be made to do this if properly set and big enough. So the question is for me is what carb can I make work the easiest? q-jet is out due to just about every one i've ever looked at being differant from one another and a complicated rebuild-so forget it. I'm not familiar with edelbock so holley it is. btw If I remember right the jets are F:68 R:72 with the lightest secondary spring. I was going to try a F:64 R:76 to increase mpg potential but I'm okay with what I'm getting and I like good throttle response.