Best 2 barrel carburetor for 318

[TIB3300]

Hello all
Hope you all good and looking forward the the summer shows and gatherings, I am

A little update on my build to the guys on here who helped me on my way

All running gear in now and after some tweaking all is good. I didn't know what to expect driving a Cortina with a Dodge V8. well its great

I keep laughing out loud when I put my foot down. The thing! will put uphill in 4th at 30mph up to 75 and cruse at 80 in fifth. I have slash cut side exist 3in pipes at the mo , and it rattles of walls and buildings, sounds awesome!

And again am back for you advice please . I want to run a two barrel, as its just a cruiser. I have a Chinese carb on at the moment that am having problems with. It will pull, tick over just fine. But just above cruising at lower speeds am getting jerking. And believe me i have been through everything else over a 2 day period

I would like to buy a new 2 barrel carb, Could you advise on which carb is the most reliable ? and where to get one ?

Thanks Tony B

[MattH]

I assume you have 2 barrel manifold currently?
The original Mopar 2 barrel carb is absolutely fine. Mine was ultra reliable and there are loads available second hand as every body junks them for 4 barrels often with little improvement.

[TIB3300]

I assume you have 2 barrel manifold currently?
The original Mopar 2 barrel carb is absolutely fine. Mine was ultra reliable and there are loads available second hand as every body junks them for 4 barrels often with little improvement.

Thanks Matt'' Yes this is what I have read since posting, Rockauto have some recons. But you don't seem to get much for your money just the accelerator plunger and new gaskets. I think I will rebuild one

And yes still on the original 2 barrel manifold foe the moment

[Dave999]

chinese carter BBD really needs the jets rods springs from an original 318 BBD put in to get a US calibration rather than a chinese guess
use better gasket and proper vaccum tube for the choke pull-off diaphragm instead of the fish tank oxygenator pipe they come with

ie use the body air horn and throttle plate + bolt in bits from an orginal to get a moderately good standard carb with no massive ware in the throttle shaft bushes

Dave

[TIB3300]

chinese carter BBD really needs the jets rods springs from an original 318 BBD put in to get a US calibration rather than a chinese guess
use better gasket and proper vaccum tube for the choke pull-off diaphragm instead of the fish tank oxygenator pipe they come with

ie use the body air horn and throttle plate + bolt in bits from an orginal to get a moderately good standard carb with no massive ware in the throttle shaft bushes

Dave

Yes this is what I did when I bought the new Chinese carb as advised by, you Dave I think? But as I said had some issues with user error. I swapped the idle screws but didn’t check the sizes, there are two different types of idle screws on these BBD carbs and yes I put the wrong ones in the Chinese carb. Resulting in way too rich mixture and Bananarama! running


The issues I have been having have been downto those two bloody mixture screws, that now I understand do the low speed running as well as the idle.

I found two vids on YouTube yesterday that are really useful that helped me understand more about these carbs and how they work, so last night and this morning on the commute to work, I adjusted the mixture screws all the way in then out ¼ a turn at a time and I nearly have the car running great!

[Dave999]

ahhh it will be a difference in taper i guess....

same stuff happend on webers as well

1.5 turns from 1 year changed to 2.5 turns on a later carb with a different taper and smaller threads

yes and Idle mixture is used for idle and off idle running
the vacuum sucks the rods down at idle and just off idle to bring in 1 mixture for transition into main circuit and when the throtle opens and the vauum decreases the rods ping up to the narrow section making more space in the jet for full power main circuit
but at idle vacuum is highest and the majority of the fuel for running comes through the idle mixture circuit

don't be alarmed if 1 mixture screw needs to be slightly different from the other. less of a THING on a v8 but defintly a thing on a six cylinder

depends on your intake and where under the carb the lowest vacuum is felt from each cylinder the 2 barrels of your 2 barrel carb do not necessarily see the same demand

PS you will also have running problems if the choke is not set right
cold it should be open about 1 bus ticket thickness which allows you to start with the throttle stop on the Fast idle section of the fast idle cam
soon as there is heat in the exhsust the choke hot box starts to pull the choke off and you move a step down on the throttle stop fast idle cam
when warm that cam is pulled out of the way and the throttle stop screw runs on its lowest step
hot it should be fully open and not flapping about

Dave

[TIB3300]

Thanks Dave'

Yes the idle screws are different to each other, but as you can see from picture the idle screws are completely different, Ive fitted an old carb now that I cleaned out and checked over all is well now.

That cheap chinese carb was part of the problem along with the timing being out was the problem, Car is running well now.

But would still like to buy a NEW! carb

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[Dave999]

holley 2bbl 500 can be adapted via an adapter to a Carter BBD manifold
and you should be able to fasion a linkage and kickdown

but get the one that has the big round section to the top i.e that fits a sensible air filter

don't get the muscle car six pack outer carbs, they are designd to work with their partners only

you won't get a new BBD from carter or edelbrock

rebuilt yes from many places but not new.....

only place where they make them new is china the more they cost the more effort the importer has put in to making it work i'd guess

BBDs were used until 91 on jeeps but the late ones have idle stepper motor and electronic fuel cut off..... unless you were taking it to bits for a decent throttle plate or some such then its probably too much hassle.. and again by that stage you may find different idle mix screw thread and taper.

a BBD is a finicky carb to set up

idle mix
accelertaor pump throw
springs
rod sizes fat and thin sections
jets
acclerator pump jet
weight and ball in the accelerator pump which dicates how much exhausts back into the bowl
Bowel vent disk and clip on the acclerator pump flat shaft, fine tunes the fuel level in the bowl under vacuum
the choke needs correct set up

this is done by setting the position of the flap
and the length of the rod that goes to the hot box on the exhuast
then you need to set idle speed and the Fast idle speed cam.
its position is set by the length of the rod from the vaccum kicker to the choke flap lever, length here is critecal to cold running set up
precise setup leads to good cold to warm running with appropriate step down of fast idle to normal idle in 2 steps as the motor warms up

get any of this wrong and the motor bogs when cold stalls when you pull up to a stop light etc

as with all carter carbs. factory set on factory motor Great..... but you need dedication to get it right on a none factory set up

which is why holley sell so many carbs


if you want all torque and no top end and can make your own adapter the 38 38 dgas weber off a V6 ford might work
you'd be bale to get a ford filter for it at least...

it will limit high rpm power but should work good in the 1000 to 4000 rpm range

as per usual imposter carb on a mopar engine will inbolve a load of messing about for throttle linkage and kickdown.


dave

[TIB3300]

I really need to meet you one day Dave

No kick down, all manwell here

I did look at a 38Dgas, but was told its no good

Looks like Holley is the way to go

[Dave999]

well BBds came with 36 mm barrels and 40 mm barels 1 9/16 or 1 7/16

many mopars used the small one


38 x 38 MM DGAS DGES doesn't seem too far off

BUT ive never done it so it could be crap


More BBD stuff than you will ever need

https://www.carburetor-blog.com/knowled ... bbd-specs/



Dave

[TIB3300]

well BBds came with 36 mm barrels and 40 mm barels 1 9/16 or 1 7/16

many mopars used the small one
38 x 38 MM DGAS DGES doesn't seem too far off
BUT ive never done it so it could be crap
More BBD stuff than you will ever need
https://www.carburetor-blog.com/knowled ... bbd-specs/
Dave

Cheers for the link, that's a keeper

[mygasser]

a mate rejetted a 38dgas weber for his 318, ran well with no issues. as far as an adapter he only needed to file/slot the carb's base plate mounting holes and it bolted right on. if you don't need a race car or to spend lots of money it'd be what i'd choose.
neil.

[TIB3300]

a mate rejetted a 38dgas weber for his 318, ran well with no issues. as far as an adapter he only needed to file/slot the carb's base plate mounting holes and it bolted right on. if you don't need a race car or to spend lots of money it'd be what i'd choose.
neil.

Thanks Mr

[mygasser]

a mate rejetted a 38dgas weber for his 318, ran well with no issues. as far as an adapter he only needed to file/slot the carb's base plate mounting holes and it bolted right on. if you don't need a race car or to spend lots of money it'd be what i'd choose.
neil.

Thanks Mr

no worries mate, at least with a weber all the jets etc are readily available too.
neil.