HI, I am wanting to replace new Carburator for my 70 Roadrunner 383 -4speed Stock rebuild!
what would be the best 650 carburator for this application,
would like some help .. ? from some one who has had to replace their carb on a 383
Want most dependable, less maintanance Carburator .!
Car has an old holley 670cfm now!
Thank you,, greatly appreciate anyones help & opinion to make my decision!

I have a carter on mine. The 68-69 road runner used Carter AVS. So you could find a used on in good shape and go that route.

I can pretty much guarantee that just about every maker of a 650 carb will get approval from someone on this list. Holley, Carter, Edelbrock, Demon, etc.

They all have their pluses and minuses. Being that you don't know carbs, a Carter is simpler than a Holley in so much as there is less you can fool with to mess up.

That said, unless you are going with a stock OEM replacement identical to the original carb you will need to mess with it. None of them are really properly tuned for your application.

So what's wrong with your original carb?

How original is the car, and which carb came on it (AVS or Holley) originally ?
Is the fuel line modified to adapt the current Holley ? That's a clue.
I replaced the original AVS on my '68 with the Edelbrock 650cfm AVS2.
Really nice carb, leaned out the metering rods 2 steps and it's better than the 53-year-old AVS.
Some guys prefer Holleys, which I use on the racecar & hot street stuff.
I personally dislike the Demons that mimic Holley 4150s, but some guys like their street carbs.
Pretty much any carb change will mean fiddling with connections, so maybe yours just needs some attention.

If your carb isn't performing well a good rebuild may be all that is needed.That being said for minimal switching a Quickfuel 650 would be my choice.Vacuum secondary or double pumper is up to you.

When I had the 383 in my B'cuda(4 spd) it originally had a Holley 650 DP that ran well for a number of years...then all of sudden it stopped feeding fuel on 1 side. No matter what I did it just quit running right. Buddy had a 3310 750 vac secondary laying around, threw that on...it ran WAY better than it ever did with the 650!

On a side note all OE carter AVS's are lean due to the discombobulated federal emission standards of the era that every mfr was struggling to keep on top of. AVS strip kits are as rare as hens teeth but some of the specialty carb mfr's have pairs of rods/jets for sale for them.

thermoquad !
just my opinion. your mileage will vary.
way back in the mid to late 80's, i wrote a program with help from the main operator, for one of the CNC machines in the shop for jets and metering rods for the thermoquad. i kept the programs and tool sheets in case i needed to make more of them. the parts i made worked perfectly, and i still use them today along with every "junk" t-quad i can scavenge for parts. only one "slight" problem. that particular machine was replaced because it got wore out. it used a perforated mylar tape for the program, and all the machines of any quality built today don't use that kind of "slightly old" technology.
all the old "tape machines" from back in that era are now recycled into some kind of soup can by now...........