340 carb size?

-
C

Competition

Well-Known Member
Joined
Apr 21, 2014
Messages
91
Reaction score
4
Location
Toledo, OH
Hello all. I tried searching for this topic, but I'm not having much luck on my phone. I was hoping some of you may have some input. I have a 69 Barracuda with the stock 1969 340 in it. I don't know anything about the engine really, when I got the car the previous owner didn't seem to know much either. He asked to keep his 750 carb that was on it, and gave me another 750 that it "didn't run as well with" when I bought the car. He let me take the car home with his carb, I put the other 750 on and the rear float is sticking, and keeps over flowing with fuel. This carb it came with is old and I want to replace it. 750 seems like a lot for a mild 340 in my opinion, but then again everything I own is new and fuel injected and tuning those cars is a little easier. I want to buy something somewhat ready to run out of the box. The engine has stock heads from what I can tell, sounds like a healthy cam, an Edelbrock dual plane intake, 1-5/8 headers, flowmasters, manual valve body 727, 4.10 gear. I was thinking of a Holley Street avenger series carb, people seem to have good luck with those out of the box. The question of it is should I go 670 or 770? I don't think I'll ever do more to this car, maybe a set of Edelbrock aluminum heads someday. What do ya think? Thanks for any help.
 
If it's a vacuum secondary carburetor, it can be tuned to run just fine on a stock 340.
 
I have a 650 on my 340 and it's to small. A 770 sounds about right IMO.
 
I have a 770 on my 360 its great, we put one on my friends 340 it works great also. vacume carbs can be changed for basically any engine size.
 
600 is plenty, will give nice throttle response and likely be more efficient than some of the bigger carbs.
 
...and for the cost of a new 600 cfm carb, he could buy a whole suite of pieces parts to modify his 750, tune it correctly, and rebuild it twice, and gain invaluable experience.
 
Ok guy's here is a real question on the 340 motors-What size stock carb came on them???????? I think that'll answer your question,Plenty guy's around here with stock 340's with 850's running strong and hard-Steve
 
It's hard to compare Carter to Holley carburetors because Carter used a different method for determining CFM.
 
get a holley 3310 750 and tune it. you won't regret it.
I ran carter afb, avs, and thermaquads on many motors over the years, they work great when tuned properly. but, they arn't as easy as a holley to setup. it took me 20 years to figure out that holley is the way to go. your 340 will respond well to a 750.
 
fishmens67 said:
get a holley 3310 750 and tune it. you won't regret it.
I ran carter afb, avs, and thermaquads on many motors over the years, they work great when tuned properly. but, they arn't as easy as a holley to setup. it took me 20 years to figure out that holley is the way to go. your 340 will respond well to a 750.
Click to expand...

One of the best carbs ever in my opinion.
 
I like the Holley 80457 600 vac secondary with electric choke for everyday drivers. It's calibrated for a late 60's era engine just under $300.


But if you want bigger, go with the 3310 at 750 CFM.
 
3310,, 750/780 cfm,, $100 at any swap meet,, kit it and luv it..

The 69 came with a 625 Carter AVS,, but the 69/70 Mopar "Hustle Catalog" showed Ma Mopar recommending the Holley 3310 - (then 780cfm),, Edelbrock LD-340, and Hooker (?) headers..

hope it helps
 
Abodybomber said:
3310 Holley,sweetheart when tuned.
Click to expand...

I don't think I have heard a better quote.

Throw a quick change vac spring kit on, add electric choke if needed for cold weather.
Tune it right and run it.
Parts are cheap, and I guarantee Holley will still be manufacturing them when I am 6 foot under.

As for your float problem, it most likely is just a needle and seat, buy a refresh kit for like 40 bucks and rebuild it your self, Holley has how to videos on their web site.
There is several excellent Holley carb books that can be bought used off Amazon cheap, buy one and learn it.
 
Not sure what stall converter you're running?

Healthy cam, manual VB, 4.10 gears.......and the possibility of "heads" down the road.....If it was me, and while I love vacuum secondary Holley's that have been givin' the proper time involved for tuning, I'd be seriously looking at a DP in the 750 range.
 
If you want a great running "out of the box" carb, bolt on a 770 cfm street avenger holley. Been there, done that and they work! I suggest putting a weaker spring in the secondary.
 
my 750 dp

best carb for my 340,
thats why you need to take yours to get tuned to your car.

 
running the street avenger 770 on my '70 340 with no problems at all .....
 
One advantage of the Holley is the fuel bowls are further away from the intake manifold then the Edelbrock/Carter types carbs. Less fuel percolation.
 
I'm running a 770 holley street avenger , runs great , better than the stock AVS performance wise , but gas mileage is not as good as the stock Carter AVS .
 
You must log in or register to reply here.
-

Back
Top