Carb Suggestions

[Winston]

Hey y'all!

Hope all is well with everyone.  I am looking for suggestions on what carb to use on my '70 340.  I am wanting to buy one that looks and performs well; I have been told that the Edelbrock Thunder Series carb is a good one to use that models the AVS that originally came on the car.   If anyone else has an opinion on this topic, please chime in.  Thanks!

Looking forward to hearing from y'all,
Winston   

[Chryco Psycho]

I would use a 750 , my perference i sHolley , the Street avenger works well or the avenger Hp

[Grancoupe]

Holley

[Winston]

Chryco,

I looked on the Holley website and found the numbers are in 670, 770, etc....would you go with the 770? 

Do you have to specify that the carb will be used on a Mopar, or are they universal?  Is there a preferable place to order one of these from? 

Thanks!

[Chryco Psycho]

get the cheapest price , I would use the 770 , they are universal but you need the linkage adapter 20-7

[Winston]

Chryco,
As you can probably tell, I'm a little wet behind the ears with this restoration stuff.      I have another question regarding the carb.  This car is being put together basically stock; it is bored .30 over, but the original cam, etc is going back in.  It will only be driven locally for enjoyment...never on a racetrack or anything like that.  Do you think a 770 is overdoing it, or for my needs, will a 670 still perform ok?  I'm asking because I truly have no idea.  Me =  :dontknow:  (on a lot of stuff!!)               

I appreciate the time.
 
Winston

[Chryco Psycho]

I assume you are using the dual plane intake , you ucan get away with a slightly smaller carb on a single plane but not on a dual plane , I would use the 770  , keep in mind the Stock 340 + 6 had 950 cfm with the 6 pack

[Winston]

Thanks for the tip, Chryco.
Is this considered a single or dual plane manifold? 

[Chryco Psycho]

That is a dual plane , you can see the runners into the heads are on 2 different levels 

[Winston]

OK, thanks.  I learn the terminology one of these days.    

I'm going to go with the 770. 

Are these things universal or is there a certain number I need to ask for when ordering?

[Grancoupe]

Sorry if i'm incorrect about this but is that a 2 barrel intake? Can't tell from the picture.

[Winston]

Grancoupe,

This is the 4-barrel intake that came on it.  I think with the orange painted masking tape makes it look like a 2-bbl.

[hotrod98]

I run a 625 Carter AFB on my near stock 340 with a 4 speed. This  carb is no longer available, but Edelbrock has a similar carb, a Thunder Series 650.  My setup has plenty of power and gets 18 mpg on the freeway.  I personally think the larger carbs tend to run a little rich and don't tune well especially near idle i.e. cruise night driving, etc. Both will work, but we all tend to go the hotrod magazine direction and end up overcarbureting. I might be wrong, but you may take a hit in the fuel mileage department with the bigger carb, which wasn't an issue until the gas price increases we've seen this year. Just my 2 cents worth.

[Chryco Psycho]

the Holley number is 80770

[DodgeFreak]

i might be wrong on this also.....but 670 and 770 are the CFM which is air flow correct?? if not correct me ...so if the 770 is air flow...not fuel flow....couldn't you just swap smaller jets in to lean the mixture if larger carbs tend to run rich which then will up the mpg ?not trying to be a smart ass i jsut haven't messed with carbs all that much and am still tring to figure stuff out...Also isn't there a fine line between having to small of jets and to big of venturas(sp?) which then would make the car run real lean??