6mustang6

ah well, i dont have the resources to rebuild it now. still runs pretty strong though.

Soaring

OK, I am just guessing here, but it sounds like your secondaries are not opening fast enough, therefore the bog.
There are a number of ways to tune the moment when the vacuum secondaries open on a Holley four barrel carb. The vacuum secondaries are controlled by a diaphram and a color coded spring. Holley makes a number of different springs with different tension on the springs. You can change the springs and change the opening moment. The color coded springs run from light tension to heavy:
If there is a bog or hesitation when the secondaries open, the spring tension is too light, go to the next heavier spring. Holley offers a kit which contains one each of the springs. When you change springs you'll note that the stock cover over the spring and diaphram is not all that easy to get to. Holley makes a special cover that makes spring changes quick. Finally, Holley also makes a completely adjustable thumbscrew operated diaphram cover. This cover limits the travel of the diaphram and therefore limits how far the secondary throttle plate can open. It makes secondary throttle opening adjustable.
Another thing you might want to consider is the size of the jets. The jet sizes will depend on what altitude you are. Check with a Holley dealer to see which jets you need for your altitude.

newownerof72

Alright,

I am going to check on getting those parts for my carb. It's going to be a couple of days, actually, probably this weekend since the better auto parts stores are in bigger towns, where I don't live.

Are you saying that I shoudl be able to buy all these in a kit, or one piece at a time?

Soaring

Well, until you can check with a Holley dealer about what jets to get for your altitude, you would not know which jets to get. If you can get the spring set, that is where I would start, but they are most likely not available at a regular parts store unless they are Holley dealers. And, even if they are, they may just sell the carbs and not the tuning parts. I don't mean to put down your carburetor, and I know a lot of guys love the Holley's, but I hate them because they are so hard to dial in. If I had your car, I would replace that Holley with a Motorcraft 4100 carb. (You do have a 4- bbl. carb don't you?)That's what Ford put on them at the factory, and for good reason. They are one tough and easy to adjust carb, and perform admirably for a street carb.

newownerof72

It's a 2 barrel. And the carb says motorcraft on it, not holley, but it came in a holley box with holley instructions, what gives?