Has anyone tuned with AF sensor or dyno a stock set of 66-67 hemi carbs on a stock motor? What jetting/meter rods used for today's fuel. Keep the stagger? I have researched, but most of the info is on 68 up carbs which are different. Thanks.

...on my 66 I used the Edelbrock600 cfm ( 1406 ?) jetting and metering rods on the primary carb. Get instruction manual and follow the adjusting flow chart for rich/lean power/idle , it depends on what cam and compression you run. I left the secondary carb be.Your results may vary ....

If I remember correctly I went with what the factory service manual for 1967 recommended. Probably best way to start and play from there, either richen or lean, most likely a bit leaner especially on the idle and cruising. If you don't have the specs I can find them.

Thanks I do have all the specs. Interesting you say leaner, because the typical convention is everything needs to be richer for todays fuel, yet it does seem like some have gone the leaner route.

I use to help a couple and later ran a Hemi in NHRA stock class back in the 1970s, I remember the jetting being the same on all the street hemi carbs from 1966 to 1971
The first car we raced (1969 GTX)had a 1968 Street Hemi out of a non CA wrecked Roadrunner in it, it ran faster with open headers with one jet size bigger in all eight jets, we never leaned it down after that

my stone stock 66 hemi car..ran perfectly with stock jetting and rods....but it was obv a tad lean WOT as the car ran faster at the drags in warmer air temps...

biggest difference i made was by modifying carbs was to lighten the air doors....car went from mid 14's @ 99 to low low low 13's @ 105 mph with no othr changes..

Just curious , but what type of modification was used?
Matt

Some racers cut weight off of the door weights, we out 5/16 nuts under the weights to hold them partially open to start with so they would open quicker on the starting line
Some of the S.S. racers would use thin diameter rubber tubing to hold the doors open in the pits and remove the tubing after the run before getting near the time slip booth or any of the techs
Lots of different ways to make them old cars go faster

i cut mine...took 3/4 of the counterweight off the front carb and half off the rear... never really experimented anymore that that though as car was beating every stock hemi car in our area..

No sorry. The Carb where constantly modified and the early 66-67 carbs are pre emission and nothing like the 68 and up carbs. Venturi bleeds, jetting and meter rods all changed. Plus what you did racing in 1970 with 1970 fuel may not equate to what a stock car needs today.

I am going to go with stock set up, but was just curious if anyone did actual testing with the early carbs since they are significantly different then the 68 and up ones. I read Jims details on what he did with his 68 carbs.

I bought a set of 10/65 carbs 4139 and 4140 for my 66 car. They are set up with the racing boosters (DC kit) and rod-jetting same as 69 carbs. My understanding this is a richer setup for the Vanke intake. I can get all the numbers for you tomorrow. I also have an extra unmolested front carb so I know that setup but not the back one. (no booster tabs on the matched pair)

How you can figure this out

Flappers

I've check several original FSM manuals on the jetting, they showed the same rods and jets in the 1966 automatic carbs as the 1970 motor automatic carbs had
Your correct on Carter making other changes to the carbs for Mopar due to emissions and other reasons I don't know about and maybe Mopar didn't update the jets and rod Carter part numbers in the FSM manuals but I doubt that

I’ll have to look again but I think my 67 book shows different numbers than the 69 &70 book. 66-67 didn’t have idle screws like 68-71 just the air valve in front. Maybe that effected the way the carb is inside.?

Getting side tracked on this. I KNOW what stock set up is on all the carbs from 66-71 including 67 CAP specific carbs. I was curious how a 66-67 carb for a stock motor would be set up for today's fuel. All the typical articles you read say you need to richen up the older carbs for today's fuel, but I am not sure that applies to the hemi carbs as much.

Cab you once made a snide remark about not reading technical manuals...I have the Carter books, and I have the FSM. So I think you need to go back and look at those FSM.

66-67 rods and jet where constant except for 67 cap. Unique was the big stagger in secondary jetting on the FRONT CARB.
68 is all state emission and was unique in rods and jets.
69-71 like 68 FRONT CARB went to square jetting no more stagger. 69-71 rods are the same along with jetting. In 68 they put the stagger in the rear carb.
But what you don't know from just a FSM, that the Carter book shows, and close examination of actual carbs with the eye towards detail is the body vent changes, plus the change in size of the venturi bleeds.
66-67 carbs like all the non emission AFB had plenty of unmetered air bleeds in the throttle bore as anti per. Those unmetered bleeds required a richer jetting to compensate.
68 up those vent no longer exist and even the top vents change. So the jetting went leaner.
Additionally, the venturi were constantly evolving with distribution tabs.

Racers took them off, including the Vanke mod. Racers also modified emulsion tube and closed up holes with solder to richen the mixture. Though probably not wise for a street car.

I guess I may just need to go get some dyno pulls done to see. Just didn't know if some on already did and had a baseline.

Good info, maybe they do need to be richened up with the 10% alcohol added to todays gas. Since mine have the factory race kit jetting to richen it up I’ll leave it. If you do dyno the engine I would like to know what you find.

Here is what the Mopar kit for your Vanke mod instructions had/did: Notice the rear carb changes besides the venturis.

Use primary venturi 58-902 and 903
Use pump shooter 48-294 (.035”) with pump link in long stroke position
Use needle and seat 25-861 (.110)
Velocity valves blocked open

Rear carb Jet 4140
Location Pump side Opposite pump side
Primary 120-159 (.089”) 120-404 (.104”)
Secondary 120-159 (.089”) 120-404 (.104”)
Meter Rod 16-440 (.0665 x .058) 16-136 (.071 x .061)

Front carb 4139
Location Pump side Opposite pump side
Primary 120-404 (.104”) 120-404 (.104”)
Secondary 120-171 (.1065”) 120-395 (.095”)
Meter Rod 16-136 (.071 x .061) 16-136 (.071 x .061)

What they came with stock
4139 uses the 58-942/3 primary and 58-347/8 secondary venturi
4140 uses the 58-946/7 primary and 58-678/348 secondary venturi
48-264 pump (.028) both carbs
25-860 seats (.1015)

I think my remark was about Chilton, Motors and other automotive service manuals specs, Not about the original F.S.M. manuals

On your deal you need to test, test and retest to get the best jetting for your carbs. using the fuel sold in your area
I had one set of 1966 or 1967 visually modified Hemi carbs that ran better than any other set we had, I traded them off to a guy who had a set of 1970 Hemi carbs on his 1966 or 1967 Hemi GTX because NHRA back then, 1973/1974, require us to have the factory carbs on the cars we raced in both Stock and Super Stock.
I was racing a 1970 Baracuda back then with a 426 Street Hemi motor in it (not a original car)and had been tossed out by NHRA tech due to having a intake manifold that had been bead blasted inside at the 1975 Winternationals
I had thrashed to get the car put together in November and December of 1974 and knew it was illegal but forgot to change it before going to Pomona for the 1975 Winternationals

out of curiosity, how did they determine it was bead blasted ? too "clean" inside without fuel residue stains ?