I have a holley avenger 670cfm and for some reason anytime a punch it to wot and let it go the secondarys stay cracked open and make the revs about 2000rpm. As long as i dont go wot they work fine. i replaced the vacuum secondary diaphram grease and checked all the linkage and been workin on it for 2 days straight took the carb of 3 times checked about everything changed the gasket checked all the vacuum hoses and get nothing. Im stumped i cant punch it or i have to turn the car off and start it again so i dont know what it is???????

 

BIG vaccum leak. Get a New carb gasket.

What spring are you using in the 4bbls?

Also make sure the quick change cover 0 ring is in place and not leaking.

 

Nope no vacuum leaks aready changed the gasket twice they wont close completely i personally think its something mechanical that might be getting binded up like the little lever that connects to the secondary diaphram rod. I was looking for idea but ive checked all around for vacuum leaks unless a small header leak will cause that. The spring that came with it is in there its a silver or aluminum color.

 

Also theres no o ring on the cover and its not the quick change secondary cover.

 

There shouldn't be any grease on the secondary mechanism.

You've probably got something misaligned/bent.

I thought all SA's had the quick change housing.

 

Avenger without a quick change?
Get it new?
If you're running more than one gasket under the base, you can warp it when you tighten it down to the manifold.

 

Theres only one gasket i dont know if its the quick change housing you take off 4 screws if thats quick but i had to use a low tension spring to pull the secondarys completely shut so right now thats working right.

 

Was this a used carb?
It sounds like the wrong vacuum unit /diaphram.
I've gone through a problem like that a long time back. Not all the secondary diaphrams are the same. There are subtle differences in rod lengths

 

So what's the verdict doc?
Patient die on the table?

 

Did anyone replace the gasket between the main body and the base before, because the trick kits come with a few different sizes and it's easy to accidentally install a gasket with slightly smaller holes.

This causes the secondaries to bind up on the gasket and not close all the way.

 

Holley Quick-Change housing.

If yours doesn't look like this, someone has messed with that SA.