If you own a vehicle with a carburetor on it, sooner or later you’ll have to rebuild
it or maybe replace some service parts!
But how do you know that you are getting the right parts?
When it comes to identifying your carburetor it’s not as easy as just saying “I have
a Holley or I have a Demon”.
It's like going to the guy behind the parts counter “I need a water pump for a V8”!
He’s going to need some more information!
Here at Holley, we've been producing carburetors since 1903 and with over a century of history
well let’s just say we’ve built a few carbs over the years.
At the end of the day you need to know the list number of your carb!
Think of the list number as a VIN for your carburetor.
The list number lets you know important things like product design, model, cfm, factory jets,
power valve size, air bleeds and everything in between.
This is all important information to have when you’re selecting a rebuild kit or ordering
your service parts.
So where do you find your list number?
Like a lot of things it’s not a cut and dry answer, but a little knowledge can go
a long way!
Let’s start by taking a look at our most common 4 barrel carbs our model 4150 and 4160
square flange as well as the model 4165 and 4175 spread-bores.
Some of these carbs have been produced for more than 60 years and have a lot of variations.
The list number for these carbs should be hand stamped on the front of the choke tower
to the right of the vent tube.
Generally the list number is 4-6 digits long and may have a suffix number such as 3310
or 80508-1.
The 3-4 digit date code is stamped directly below the list number and in some cases you
may even be an OEM part number stamped above both of these numbers if it was a factory
part.
Be careful not to confuse the casting number with the list number!
Holley casting numbers have an alphanumeric sequence such as 6r1234 this is not the list
number.
The casting numbers are alphanumerical and can be identified by the fact that they are
raised or cast into the part and not stamped.
What if you find that your carb doesn’t have a choke tower!
More than likely someone has cut and removed the choke assembly for performance gains.
Unfortunately they also removed any numbers enabling you to be able to identify your carburetor.
You can get some clues by breaking down and inspecting the carburetor but it will be hard
to determine its true identity.
If you have an early 4150HP or a newer 4150 ultra XP it’s pretty straight forward.
Holley 4150HP and XP carbs come right from our factory without choke towers.
HP models can be identified by the 6 raised bosses cast directly into the side of the
main body.
On early series carbs without screw in air bleeds look for the list number to be stamped
on the top.
On later models with screw in air bleeds or and on the 4150 Ultra XP’s the list number
will be stamped or laser etched on the throttle lever side of the main body.
These list numbers are 4-6 digits and may contain a suffix number, 80528-1 would be
a good example.
Once again the 4 digit date code should be directly below the list number.
Now let’s look at the popular 2300 model 2 barrel carbs.
This one can be a little tricky since the list numbers could be in any one of 4 possible
locations.
One place it can be found is on the choke tower like our previous carbs, if it’s an
earlier race 2 barrel and is not machined for a choke plate you can find it stamped
on the top next to the choke tower.
Our newer 2 barrel ultra XP’s will not have a choke tower and the numbers will be laser
etched on the top.
If you’re fortunate enough to own a six pack set up, list numbers for the outboard
carbs can be stamped on the choke tower or the back side of the main body.
Again the list number will be 4-6 numeric digits with a date code below it.
Some models may also have an OEM part number above the list number as well.
Getting into our 4500 dominators you will find 3 generations of carburetors.
Early first gens are easy to identify by the raised rings around the venturies and the
list number will be stamped on the top.
2nd gen models will have the numbers stamped into the throttle side of the main body.
And our 3rd dominators are easy to id with the 4 built in threaded air pan bosses.
List and date code numbers for the gen 3 can be found laser etched on the throttle side
of the main body.
Once again look for a 4-6 digit list number with a 3 or 4 digit date code below it.
A typical dominator list number would be something like 8896-1.
If you have one of our popular street demon carburetors you will find the list number
and date code laser etched into the rear of the air horn assembly.
Its 4-6 digits and may be alphanumerical for example you could find a 1901 or 1901bk.
A 5 digit production code can be found after the list number.
And finally if you have a modular demon 4 barrel it will have an alphanumeric list number
up to 9 digits long, laser etched into the air cleaner flange.
With a 5 digit production code to follow.
If you don’t find a number laser etched in the flange that means your carburetor was
manufactured prior to Holley’s acquisition of Demon.
Identifying these earlier carbs can be a bit tricky and it may be necessary to contact
Holley’s tech service for more help.
Be sure and have the carburetor handy when you call so you can answer any questions our
tech guys might have.
Once you have positively identified your carb using the information I’ve given you, simply
go to the website at Holley.com and enter your list number into our handy carburetor
kit selector.
And we’ll take the guess work out of selecting the correct rebuild kit for your carb.
We hope this video was helpful!
For more information and tech tips go to Holley.com and click on the support tab at the top of
our webpage or you can check out the Holley page on YouTube for more how-to videos.