Need help identifying Holley Carb

[tony-muscle]

I have looked everywhere and I still can't fully identify the Holley carb in my 351C. Obviously is not the original one because the date code indicates 1993. Below the date code it says "6R 4585 B", but this has not helped with full ID. The air horn has "3350" and what it appears as a scratched set of numbers. From what I read thats the list number that should tell me what it is. So the question is, can someone identify it based on pictures and numbers? My guess would be a 4160 600cfm, but would like the experts opinions.

Also, why will that # be scratched? were they hiding something?

Thank you.

 

[Totalled]

Top number is a list number. try to read it, or take a close up so we can. Dual metering blocks would be a 4150 series.

 

[mustang7173]

tony-muscle,

Sometimes they have the carburetor number stamped on the base, where the butterflies are mounted. This might require removal of the carburetor.

mustang7173

 

[tony-muscle]

I looked at the scratched numbers with a loop and side lighting. I think the first digit appears like '8' and the last two '78' or '73', so probably '8XX78' or '8XX73'.

Could it be that they scratched the numbers because they may have changed the jets and springs so it is not longer matches the original specs?

 

[Jeff73Mach1]

Who knows why they may have done such? It is a vacuum secondary Holley 4150. To determine the flow, you could remove it and measure the bore sizes.

Does it have 4 corner idle adjustment?

I'd bet it is a 750 cause everyone knows you have to have a holley 750 to go fast

 

[Mister 4x4]

I'll bet all that carbon build-up from backfiring hasn't helped a bit. I'd probably just replace it with an Edelbrock 1406 and be done with it.

 

[MotoArts]

A quick google search of "holley list 3350" gets this:

https://www.holley.com/products/fuel_systems/carburetors/avenger/street_avenger/parts/0-80670

 

[tony-muscle]

I looked at that one last night and it looks very close, but never saw a mention of the "3350" in that page.

Within the Street Avenger class they have 8 different part numbers: 0-80570, 0-80670, 0-80770, 0-80870, 0-81570, 0-81670, 0-81770, & 0-81870. It could be that my last digit is a zero instead of 3 and 8.

 

[MotoArts]

Probably have to contact Holley to be certain.

The list number on the choke horn is what I ALWAYS use to ID a Holley carb, or at least know what it was born as (since components can be changed through its life).

Yep, I see no other reference to 3350 anywhere in the online catalog, and did notice that there weren't any other pertinent hits in the google search. I work with auto parts daily, and often find these "weak" listings or dead ends when researching fitments or applications.

Holley's list number chart is big. I wouldn't be surprised to learn that the 3350 has been superseded in their part numbering system, or something to that effect. Seeing the numbers physically eradicated above the 3350 on your carb is odd, but who knows what they have done at the factory.

Just from the external physical properties, I'd guess that yours is the 670. Just my opinion, though.

Another way to check is to verify your carb internals (jets and such) with what they list in the parts section here:

https://ac17cb7e3cc3506f0d23-7386afb7d61f5e5af0e5a817d2877bfe.ssl.cf1.rackcdn.com/techlibrary_carb_numerical_listing.pdf

or here:

https://ac17cb7e3cc3506f0d23-7386afb7d61f5e5af0e5a817d2877bfe.ssl.cf1.rackcdn.com/199r10219-3rev4.pdf




Hope this helps ::thumb::

 

[tony-muscle]

I think we are very close. If you look carefully at my first picture, on the secondary side by the base of the carburetor you see a carved "670" that appears hand written.

 

[TommyK]

The 3350 number is the date code. That carb was built on the 335th day of the year 2000. It is an early street avenger. As jeff has already advised, measure the venturi diameter and the baseplate hole diameter to determine what cfm it is.

The early SA carbs suffered from casting deterioration issues and Holley will usually replace them if they fall within a certain date range if you ask them nicely.

 

[tony-muscle]

The 3350 number is the date code. That carb was built on the 335th day of the year 2000. It is an early street avenger.

Tom, if thats the case why would it have a date code indicating "93" as shown in the 3rd picture. Could it have been rebuilt with different parts?

 

[FastE]

Looks like a street avenger as said. I think you are dead on with it being a 670. I am running a 770 S.A. with a milled choke housing and really like it. I had some issue after about 6 months of use just weekend cruising and some track time etc...pulled it apart and did some fine tuning, milled the choke housing and blended the main body and it really performs well now.

 

[tony-muscle]

I have an issue now that seems carburetor related. When I am going "slow" near idle, and hit the gas slightly it kind of bogs down - it takes about 3-5 seconds to go back to normal. However, if I hit the gas hard it goes well. Could it be something with the accelerator pump? It seems that gas is missing when slight acceleration is applied.

 

[FastE]

I have an issue now that seems carburetor related. When I am going "slow" near idle, and hit the gas slightly it kind of bogs down - it takes about 3-5 seconds to go back to normal. However, if I hit the gas hard it goes well. Could it be something with the accelerator pump? It seems that gas is missing when slight acceleration is applied.

Sounds like you could have a bad eccelerator diaphram. You might try shooting some B12 carb cleaner down the airbleeds. If you are going to look at the pump diaphram you will have to pull the front bowl and metering

block anyway, shoots some B12 through all of the passages and blow them out with air( wear your safety glasses) you will get carb spray every where so don,t do it near your paint, preferably on a bench. I have found if you keep these carbs cleaned out they really will last you and give you trouble free performance.

 

[tony-muscle]

I will eventually take the carb down to clean and rebuild. That's why I wanted to know the model so I buy the right kit.

Talking about carbs, I will throw another question out there because I am learning so much. This question is regarding the throttle cable. When I press the gas pedal all the way I get the butterflies about 1/2 open? The obvious issue here is that the cable is either too long or it has lengthen. BTW, the only thing below the pedal is the factory carpet. Since my carb was likely added at a later time could it be that the location of the throttle attachment changed with respect to factory? I don't want to buy a new cable to figure it still too long. As a temp measure I may try to shorten the cable this weekend, but that will rise the pedal a bit. Thoughts?

 

[tony-muscle]

I will eventually take the carb down to clean and rebuild. That's why I wanted to know the model so I buy the right kit.

Talking about carbs, I will throw another question out there because I am learning so much. This question is regarding the throttle cable. When I press the gas pedal all the way I get the butterflies about 1/2 open? The obvious issue here is that the cable is either too long or it has lengthen. BTW, the only thing below the pedal is the factory carpet. Since my carb was likely added at a later time could it be that the location of the throttle attachment changed with respect to factory? I don't want to buy a new cable to figure it still too long. As a temp measure I may try to shorten the cable this weekend, but that will rise the pedal a bit. Thoughts?

Worked on the throttle wire issue on Saturday. I took the wire and looped it around a bolt tightening it between washers and a nut. The loop shorten the wire and now I can get to WOT. A quick not pretty fix.

I wonder how long it has been without reaching WOT. That means that it has not been pushed that much for a while. Today I pushed the pedal down to WOT many times to hopefully give it some needed use.

 

[1973grandeklar]

I will eventually take the carb down to clean and rebuild. That's why I wanted to know the model so I buy the right kit.

Talking about carbs, I will throw another question out there because I am learning so much. This question is regarding the throttle cable. When I press the gas pedal all the way I get the butterflies about 1/2 open? The obvious issue here is that the cable is either too long or it has lengthen. BTW, the only thing below the pedal is the factory carpet. Since my carb was likely added at a later time could it be that the location of the throttle attachment changed with respect to factory? I don't want to buy a new cable to figure it still too long. As a temp measure I may try to shorten the cable this weekend, but that will rise the pedal a bit. Thoughts?

Worked on the throttle wire issue on Saturday. I took the wire and looped it around a bolt tightening it between washers and a nut. The loop shorten the wire and now I can get to WOT. A quick not pretty fix.

I wonder how long it has been without reaching WOT. That means that it has not been pushed that much for a while. Today I pushed the pedal down to WOT many times to hopefully give it some needed use.

Tony, I have a Holley 600 CFM installed on my 302 and had the same throttle wire issue. It would only open to about 1/2 throttle. What I did was remove the throttle bracket attached to the intake and bolted it onto a metal plate to move the bracket back. This looks OEM and I have no fear of the bolt and washer method coming loose. If I go back to the stock 2V carb, I simply remove the adaptor plate.

Do you have an automatic transmission? I have an FMX automatic and had to replace the primary shaft in my Holley so I could properly incorporate the kickdown rod connection.

 

[tony-muscle]

Tony, I have a Holley 600 CFM installed on my 302 and had the same throttle wire issue. It would only open to about 1/2 throttle. What I did was remove the throttle bracket attached to the intake and bolted it onto a metal plate to move the bracket back. This looks OEM and I have no fear of the bolt and washer method coming loose. If I go back to the stock 2V carb, I simply remove the adaptor plate.

Do you have an automatic transmission? I have an FMX automatic and had to replace the primary shaft in my Holley so I could properly incorporate the kickdown rod connection.

I looked at that bracket and thought that could be an option. I may do that later, but this weekend I wanted a quick fix to "feel" the real power. The kickdown rod is connected (you can see in picture on first post), but I don't know if properly adjusted. I have not gotten to investigate how to adjust the kickdown rod yet.