While exorcising some electrical gremlins, one little devil (see the electrical board), the electrically heated choke, lead me to discover that the secondaries on a Holly 4bl are not opening.

There is a missing linkage rod that opens the secondary butterfly during wide open throttle. Where can I get these rods?

As a side note I have no clue what model, size, year, or anything about this carb other than it is not vacuum operated. There is no tag on it, or numbers that I can find.

Secondly I don't understand how to provide a photo of this item. Perhaps someone could help an old geezer.

Pull air cleaner off, and on the side where the primaries are, the numbers are on the airhorn (contains the choke plate)...

There will be two sets....

either old style/OEM "List-4221-0" and another number below that

or Aftermarket "0-8007" and another set of numbers below that

We need the 'List' or "0-####" numbers...

Next after that I suggest getting a Holley book from your local book store or Amazon... (if you're playing with a Holley, you're gonna need a book...)

Either HP Books "Holley Carburators, Manifolds, & Fuel Injection" by Mike Urich & Bill Fisher

or an older book "Super Tuning and Modifying Holley Carburators" by Dave Emmanuel

-D.Idiot

Thanks D.I., Reding is a little easer than working inverted under the dash...

There is a number repeated on each of the castings holding the air horn: 45R107. additionally a second number is located on the upper face of the main casting, or body, on the right side of the secondary half: 6F4208.

Is this information helpful?

Carb ID number up update.

Got a little bit of a red face here, I misunderstood your clear instructions. After dowing additional coffee the light came on. The top number is 8007, the bottom 0153

Your Holley is an 8007, 390 cfm 4 barrel Vacc. Secondary Carburator...

The linkage rod that actuates the secondaries is on the 'choke' actuation side of the carb under the vacc. pod... if the pod is missing it's diaphragm and rod... then you'll need to get another one 135-2 (this is length specific you won't be albe to 'scavenge' one out of just any carb)... if you're spending the money I would also highly suggest getting a quick change secondary spring kit (so you can quickly change when the secondaries come in with the removal of two screws, rather than the most evil teardown proceedure endured by a carb tuner...) kit number 20-59, and a set of springs 20-13 (most guys on the board run the purple or the yellow spring depending on the build... you can also lock out the secondaries with the black spring for tuning the primaries if needed).


good luck,

-D.idiot

Thanks D. I.,

Two pots of coffee are better than one...


Goggle yielded the following site covering Model 4160 titled "installation and adjustment Instructions":

holley(dot)com/data/Products/Technical/199R8108-2.pdf

That site is just what I needed, nine pages of photo's, and instructions. It is like going to Carburetor University. Panic attack is now over.