[reflog]

Originally Posted by red65mustang

what's the CR and cam at .50 and intake on this motor????
(and do you have a open spacer on it)

what really jumped out at me is you only have 14Hg at 2,000 rpms with no load!!!!

that's plenty of intake stroke piston speed and piston air displacement at 2,000 to make alot more Hg.....
(if the rotating assembly is sealing correctly)

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Don't know how to determine what you are asking. I do know that all of the vacuum readings were with the secondaries flooding. I am not sure how that would affect the vacuum though. The standard CR on this motor is 10:1 but at .50 of the cam is beyond me.

Steve

[Nothing's Easy]

I gave up on my 670 and went to an Edelbrock 600 (1406) also. Worked fine on my automatic but when I converted to stick shift there was some hesitation on acceleration but adjusting the accelerator pump and a smaller rod / stiffer spring change (kit 1487 and follow the calibration chart), it works awesome now. Its super easy to tune and just... WORKS!!

[SSedan64]

Have you checked to make sure your carbs float isn't leaking & filling up with fuel? What type of float does the Avenger come with brass or the poly.

[Sixtyninemercury]

Originally Posted by reflog

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Don't know how to determine what you are asking. I do know that all of the vacuum readings were with the secondaries flooding. I am not sure how that would affect the vacuum though. The standard CR on this motor is 10:1 but at .50 of the cam is beyond me.

Steve

With a rich idle your vacuum readings will be low because the motor is not running efficiently. If your secondary's are flooding then it is running horribly rich. The motor isn't getting enough oxygen for the correct combustion process so the umph is gone to push down the pistons like normal - so that will affect engine vacuum. I think that poster is meaning at ".050" - which I take to mean he is asking your cam's duration.

Have you fixed your flooding problem? That is your carb's problem.

[red65mustang]

I'm simply asking what is the camshaft duration?
(most commonly expressed as XXX/YYY @ .050).....
and are you using a dual plane or open plenum intake?
and what rpms is the idle set at that your reading only 7-8Hg?

without knowing the camshaft duration,,,,
to know what the typical/expected operating Hg values should be when tuned up with that cam,,,,
there are just way to many possible causes to post possible reasons for your your extremely low Hg readings.....

[Nothing's Easy]

I had this same problem with my street avenger and eventually just put it on a shelf.. I was bored and tore it apart yesterday, 3 out of 4 grooves (must be the idle circuit??) in the base plate were blocked by little walls left over from the plating process. Someone has posted pictures of this before but I can't find the thread.

[reflog]

Originally Posted by Sixtyninemercury

With a rich idle your vacuum readings will be low because the motor is not running efficiently. If your secondary's are flooding then it is running horribly rich. The motor isn't getting enough oxygen for the correct combustion process so the umph is gone to push down the pistons like normal - so that will affect engine vacuum. I think that poster is meaning at ".050" - which I take to mean he is asking your cam's duration.

Have you fixed your flooding problem? That is your carb's problem.

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Sorry I haven't been back for a while. I have been trying to get the vette back together before the snow hits me in the *****.

Back to the Holley problem. I found out that the damn thing was flooding do to a fuel pump that was pushing out between 9 and 12 #'s of pressure. I replaced the fuel pump with one that only puts out 6 #"s and I have finally been able to get the timing, idle and everything else back where it should be. My only problem now is that "I" screwed up the fast idle setup and being I have the mentality of a rock, I am not sure how to get the thing back to where it should be. At start up it will not hold on fast idle. When it gets warm the thing will idle fine. I have set the fast idle screw in about every position with no sucess.

Steve

[spinn]

is this carb or timming. sounds like timming ...you running a vacuum advance.

as you pull away your vacuum drops, a vacuum advance should see the drop , advance the timming , and increase the idle.

all the while providing ample time to burn the fuel the carb is suppling.

there are different fast idle cams for the choke.

[reflog]

Originally Posted by spinn

is this carb or timming. sounds like timming ...you running a vacuum advance.

as you pull away your vacuum drops, a vacuum advance should see the drop , advance the timming , and increase the idle.

all the while providing ample time to burn the fuel the carb is suppling.

there are different fast idle cams for the choke.

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Don't know if you meant this for me or not? It is not a problem when the vehicle is warm and I pull away, so I don't relate it to the vacuum advance or timing. It only does it when I first start it up. Choke is semi-closed but the fast idle does not hold when I first start it. I have to find someone who knows how to set the fast idle and then it should be OK all the way around. I've checked all the current fast idle cams I have in stock and three are the same. One has less ramp to it but I don't think that will cure the problem.

Steve

[Regal Beagle]

I find it amusing that all the guys on this forum that bash BG, Edelbrock and every other carb manufacturers product are strangely absent from a thread that shows the short comings of their beloved Holleys.
Come on guys, its time to ride to the rescue of the carbs that can do no wrong!!!

[staleg]

Fuel pumps can cause flooding problems when used without regulator (like the Carter 4070 for example), even if they are not supposed to put out more than 6 psi.
If you still haven't solved your problem, put on a simple regualtor, a fuel pressure gauge and adjust the pressure down to 5 psi.

[spinn]

why floats?

with the float screw out , is fuel running out the side?

are you running avacuum advance?

if no, your on your own for driveabilty. lack of it, will destroy part throttle driving.

i have never got an acceptable driver tune , from a fixed mechanical timming curve. great if you plan to floor it all the time.