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Discussion Starter #1
I have a Edelbrock Performer Carb #1406. I belive it has vacuum secondaries? I no longer have a vacuum advance distributor though. Its MSD, with centrifugal advance. So are my secondaries not opening? It doesn't seem like it 90% of the time. Even when I mash the accelerator.

I rarely here the engine open up. Even though the performance seems to be OK.
 

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The two are really unrealated. One of several ways to gain timing advance is to use vacuum as a trigger. Now that you are not using vacuum should not affect how the carb works. Not sure why you think your secondaries are not opening up if performance seems OK?
 

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Vacuum advance & vacuum secondary really don't have anything to do with each other.

The Edelbrock has a mechanical linkage to the secondary butterflies, but also has an "air valve" that doesn't permit airflow until it is demanded. You might want to check that your linkage is properly adjusted to allow full opening....
Read Johnpro's Doofus on this matter
 

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First thing, do you have enough travel in your linkage, you're not bottoming out too soon?

I have that carb also. It has mechanical secondaries on it. But it also has an air control valve that you see over the rear secondaries. The opening of this valve is controled by engine vacuum. If your engine doesn't need the extra flow, the secondary air control will not open.

With any carb that relies on engine vacuum to control the secondaries, if set up correctly, you won't feel them open. If you do feel a sudden surge when they open, they're opening too late. What you're experiencing is the power dropping off.
 

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Discussion Starter #5
This is the only car I've owned so I don't really know what to expect.

There is a point when you mash the accelerator where the engine roars. I hear it all the time on my dads 351 and on my friends 302 5.0. I've only heard it once on my 289 4v and I hadn't mashed the accelerator, I just gave it a little to much gas coming off a complete stop.

Maybe I just cant hear it over my exhaust.

Sorry, Im a newbie.
 

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Discussion Starter #7
hmm, I don't think the throttle lever thing is working correctly.

It's half open just sitting there. Engine isn't even started.
 

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Discussion Starter #8
Here it is guys... what do YOU think?

http://members.cox.net/tsmumpow/lever1.JPG
http://members.cox.net/tsmumpow/lever2.JPG
 

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Like Clone said, read my doofus post from yesterday. Here's a couple tips, though, and part of the reason it took me so dang long to figure out I was using my secondaries.

It's not enough to operate the linkage by hand. I could open the secondaries from pulling on the linkage under the hood, but when the pedal was pushed to the floor, they weren't opening. Use a helper. Have him put the pedal to the floor. Then look on the passenger side of the carb at secondary linkage. There's a little stop on the linkage that will come around and contact the base of the carb. If the pedal is floored, but the "stop" doesn't contact the carb base, you're in the same boat I was in ... running around with a really cool looking 2 barrel /forums/images/icons/wink.gif.

NOTE: This must be done with the engine warmed up, and you may very well flood the carb by doing it, but at least it will be done. Even when adjusted correctly, the secondaries will NOT open when the engine's cold.
 
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