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Original Message
Joe, you are listening to the wrong guy.
By Styleline58 - 07/25/2001 7:32:34 PM; IP 216.244.25.66
>I guess my camshaft is to radical to run these carbs.>

What is with the defeatist attitude, Joe? You want this thing to run right, dontcha? Dig this:

Idle vacuum does not operate your secondaries. Manifold vacuum does not operate your secondaries. The info you have been given is crap. Stop thinking of the term "vacuum secondary" as a technical term and think of it as a marketing term. "ZAP-ZOWIE secondary" would be as accurate. I will explain.

The secondaries on those Ford carbs are controlled by a servo. The secs are held closed by a spring working to push the servo down. The servo has a rubber membrane. The upper side of the membrane is sealed in a chamber that is open at one small point to the inside of the passenger-side primary venturi. Airflow through this venturi causes a low pressure area to develop at the opening to the secs servo chamber. As airflow increases, the pressure in the servo cavity decreases, it becomes negative to ambient. When the negative pressure is enough to overcome the force of the spring and the friction of the shaft and stuff, the secs begin to open. More airflow, more opening force. The action of the secs is controled by airflow though the primary, not by manifold vacuum. You can test this by removing the carb, opening the primary and blowing compressed air through the primary past the port for the secs. The secs will open. Meanwhile, the manifold is far away.

When you floor it, manifold vacuum drops. At WOT, it's less than 2 inches.

My engine, a 352, has about the same vacuum at idle as yours does. It has a big cam. It also uses a BT DP intake with a 3310. I use the lightest spring in the secs. Works great. Pulls hard to 5K, then pulls harder. I shift a 7K to save the stock rods and cast pistons. Read about it here:
http://home.earthlink.net/~tcrocker/

Your idle vacuum IS telling you something. It's telling you to use no higher than a 5.5 power valve in those Ford carbs. Use the stock jetting for now, get the lightest Holley secondary springs. Put them on and tell us who this "expert" is so we know who to avoid when we call Comp for info. I am serious, this guy was not helping you. Email me privatly if you want to talk more about these carbs.
This thread, so far...
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Collapse <a href=../ForumFE/reply.aspx?ID=7331&Reply=7331><img src=../images/reply.png width=30 height=10></a>&nbsp;<a href="#" id="anchor7331" onclick="return false;">Holley Carb problem part two</a>&nbsp;-- <font color=#0000ff>Joe, <i>07/24/2001</i></font><script type="text/javascript"> new HelpBalloon({ dataURL: 'replyb.aspx?ID=7331', contentMargin: 60, icon: $('anchor7331') }); </script>  Holley Carb problem part two -- Joe, 07/24/2001
 RE: Holley Carb problem part two -- RJP, 07/24/2001
Collapse <a href=../ForumFE/reply.aspx?ID=7340&Reply=7331><img src=../images/reply.png width=30 height=10></a>&nbsp;<a href="#" id="anchor7340" onclick="return false;">RE: Holley Carb problem part two</a>&nbsp;-- <font color=#0000ff>Will, <i>07/25/2001</i></font><script type="text/javascript"> new HelpBalloon({ dataURL: 'replyb.aspx?ID=7340', contentMargin: 60, icon: $('anchor7340') }); </script>  RE: Holley Carb problem part two -- Will, 07/25/2001
Collapse <a href=../ForumFE/reply.aspx?ID=7343&Reply=7331><img src=../images/reply.png width=30 height=10></a>&nbsp;<a href="#" id="anchor7343" onclick="return false;">Just adding to the chorus of snorts here.</a>&nbsp;-- <font color=#0000ff>Styleline58, <i>07/25/2001</i></font><script type="text/javascript"> new HelpBalloon({ dataURL: 'replyb.aspx?ID=7343', contentMargin: 60, icon: $('anchor7343') }); </script>  Just adding to the chorus of snorts here. -- Styleline58, 07/25/2001
Collapse <a href=../ForumFE/reply.aspx?ID=7344&Reply=7331><img src=../images/reply.png width=30 height=10></a>&nbsp;<a href="#" id="anchor7344" onclick="return false;">RE: Just adding to the chorus of snorts here.</a>&nbsp;-- <font color=#0000ff>Joe, <i>07/25/2001</i></font><script type="text/javascript"> new HelpBalloon({ dataURL: 'replyb.aspx?ID=7344', contentMargin: 60, icon: $('anchor7344') }); </script>  RE: Just adding to the chorus of snorts here. -- Joe, 07/25/2001
Collapse <b>Joe, you are listening to the wrong guy.</b>&nbsp;-- <font color=#0000ff>Styleline58, <i>07/25/2001</i></font>Joe, you are listening to the wrong guy. -- Styleline58, 07/25/2001
 Very well put. n/m -- Will, 07/25/2001
Collapse <a href=../ForumFE/reply.aspx?ID=7360&Reply=7331><img src=../images/reply.png width=30 height=10></a>&nbsp;<a href="#" id="anchor7360" onclick="return false;">RE: A few words on power valve selection</a>&nbsp;-- <font color=#0000ff>RJP, <i>07/26/2001</i></font><script type="text/javascript"> new HelpBalloon({ dataURL: 'replyb.aspx?ID=7360', contentMargin: 60, icon: $('anchor7360') }); </script>  RE: A few words on power valve selection -- RJP, 07/26/2001
 The idle vacuum is indicative of what it will be.. -- Styleline58, 07/26/2001
 RE: Just adding to the chorus of snorts here. -- Will, 07/25/2001
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