carb size for 340 4-speed

[Dartswinger70]

Greetings all, I'm restoring a 70 swinger340,and am intersted in what cfm the
340 4-speed swinger carb was from the factory as I didnt get the original carb when I purchased the car,(I got a junk leaky thermoquad which I rebuilt I dont know how many times untill I finally gave up)I ended up running a 600 holley but want to go back to the original carter style carb,was thinking of an edelbrock performer. ANYWAY ANY INFO WOULD BE APPRECIATED!
\ tHANKS R.W.

 

[mullinax95]

Here is something that might help. Click on Carburetor Application Chart

http://www.edelbrock.com/automotive_new/mc/carbs_acc/carbs_access_main.shtml

 

[Bill McLeese]

Hi this is Bill I,am running a 340 hiperformance in my 73 scamp.I had one of the carbs on mine when i got it.It would not stop leaking .I put on an edelbrock 650 cfm that is what they told me.It is a good carb needed a little adjusting but give good mileage and has the get up and go when you want it good luck

 

[70coyoteduster]

The original carb was a 625cfm Carter AVS.

 

['64 Cuda]

I think I have an original carb from a 340. Don't remember whether it's from an auto or manual trans. I'll have to dig around a bit. I'd probably sell it if you're interested (& if I can FIND it!). :tongue3:


:burnout:

 

[snook]

If this is a stock 340 street car, the 625 AFB is what you want. If you race the car, try the 800 AFB.

 

[mullinax95]

This carb calculator will set you up on what size carb you need to run.

http://www.csgnetwork.com/cfmcalc.html

 

[Dartswinger70]

Thanks to all who replied,saved me alot of research time,thanks again

 

['64 Cuda]

I used to run a 273 with stock heads, Isky valve springs, headers, Offy single plane manifold & street hemi grind cam. I had a Holley 600 cfm 1850 carb on it, which would be more carb than the engine needed if you go by what the calculator says.

One day I stuck a 780 cfm 3310 Holley that my brother had laying around on it & took it by my street racin' buddy's house to give him a ride. I already had 3.91 gears in the rear & he said it felt like I had put in an even deeper set. The 780 gave the car power it hadn't had before. I don't know, maybe the 600 carb just wasn't set up quite right, maybe the 780 was just the "magic combination" for the car. All I know is that the calculations said that the carb was way too big & the real world said different. Since you're working on a '70 model, I think it needs a six pack! (Of course, I think they all need a six pack, so I'm a bit biased!)