Dual quads versus big hammer!!!...

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j par

j par

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The two Holley 625 street demons (not typical Holleys) are starting to give me a little bit of a hard time... I've got to verify my O2 sensor is working correctly. I'm going to try and recalibrate it tomorrow. If that doesn't work it's getting sent back. I had my AF gauge start going crazy and I ordered a new O2 sensor but it was a cheap one from Amazon and I'm suspect of it as well... I've done just about everything to stop the hesitation with standing literally buying a wheelbarrow to pour fuel in... I have the biggest squirters available on the highest setting on the pump shot. I went two stages leaner on the primary Jets that didn't seem to make a difference. I went from the factory step up Springs to the weakest Springs and still cannot get the car lean or close to it... The highest I see on the O2 sensor is 13.2 at idle and drives around at 11 and 10...
I used the direct manifold vacuum Port as it smaller in my gauge plugs in..
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Right now I plan on buying the next step smaller primary Jets (I believe the smallest available) and I'll look and see that the biggest metering rods available
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That's where the vacuum is at idle on both carbs.. when I goose the gas it drops a little and then goes up another 10 lb or so... I'm reading a relatively study for the cam 13 at idle but it does move around a little bit. It feels pretty good under power but if it's giving it to quick it stumbles. of course it has its moments of greatness when I hurry up just a little bit let go of the clutch and give two it comes on very hard.. I'm just seeing a lot of low numbers on the O2 sensor. Also I've tried various step up Springs and nothing seems to make a difference. The last thing I tried was the weakest Springs hoping they would drop down into the Jets and stop the fuel but no go still rich...
 
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318willrun said:
no hammer, sell the Demons and bolt your eddies back on
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Well these do have their moment of greatness like I said. I'd like to see if I can't do something to get these sorted out. I need to verify that gauge.. also remember reading I thought somewhere on the Edelbrock that those step up Springs and their numbers are only half numbers of what the vacuum is? As in when it's a number 5 it's for 10 lb of vacuum. which kind of makes sense cuz it only goes from 3 to maybe like 7 or 8... What's your problem
 
j par said:
Well these do have their moment of greatness like I said. I'd like to see if I can't do something to get these sorted out. I need to verify that gauge.. also remember reading I thought somewhere on the Edelbrock that those step up Springs and their numbers are only half numbers of what the vacuum is? As in when it's a number 5 it's for 10 lb of vacuum. which kind of makes sense cuz it only goes from 3 to maybe like 7 or 8... What's your problem
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What's my problem?? LOL :realcrazy: Ok. I'll say "throw your A/F gage out the window. That is for good running/performing cars that you are looking for the "fine lining".
 
Did you try the factory step rod springs after you changed the pump shooter and primary jets
 
Now see I don't think these plugs are reading with the A/F gauge is..
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#1
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318willrun said:
Don't take this wrong, but Never. I don't have tuning issues either....
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You probably don't, practice makes perfect.
I added 02 sensors 2 years ago, I found it as a very fine tuning tool.
I was within a half a point throughout the range just by feel and reading plugs. Something I learned over the years by a very good teacher. myself. LOL
 
fishmens67 said:
I asked a question, an answer would be nice
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Sorry yes I went up some spring sizes but not all the way to factory. I think I want to start back with a factory setting tomorrow. Or even go one step larger to the silver Springs. Again you are noticing that heavy vacuum..
 
Also I forgot to say that I did verify by not connecting the two carburetors together that the secondary flap door smacks open when activating one carburetor at a time....Maybe there will be something to drilling...
 
I'm almost curious to hook them up Progressive.. I just don't like the idea of cruising like the freeway with just the back carburetor running. I know it doesn't work this way but I get the feeling that the rear will be rich in the front will be lean...
 
I might just possibly take those choke flaps off completely. They're not doing anything and I don't have them hooked up. I just end up having to take a pin off when I'm making adjustments to the springs and metering rods..
 
318willrun said:
no hammer, sell the Demons and bolt your eddies back on
Click to expand...
I have to disagree. I think the matching Demon's will be a better setup when jpar gets them tuned.
It takes time when working with something new/ unknown.
 
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