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Old 04-30-2014, 07:06 PM   #1
c10seth
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Too Rich: SBC 670 Holley Street Avenger

Hey, all.

I have a 360ci SBC with an Edelbrock top end kit #2022. Compression ratio is about 10:1. 93 octane fuel with Stabil left over from winter storage.

http://www.jegs.com/i/Edelbrock/350/...FcURMwod_xwA4A

I have the timing set to 12* BTDC at idle and 36* of Mechanical timing ~2,500 RPM (Vacuum advance disconnected & plugged). I installed a fresh set of spark plugs gaped to about .040" and within about 20 min of idling the truck wouldn't idle any more because the plugs were fouled out. I was getting between 5" and 10" of Hg at idle and I know it should be higher than that. A knowledgeable buddy of mine suggested it could be the Power Valve (PV) or my floats are set too high. I think my floats are ok as the the fuel level is just below the threads, from what I can see. As anyone had any issues like this? Thank you.

Kindest Regards,

c10seth
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Old 04-30-2014, 08:12 PM   #2
geezer#99
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Re: Too Rich: SBC 670 Holley Street Avenger

Hook your vac advance up to manifold vacuum, your idle and vacuum will come up, turn down your idle and adjust your mixture screws. Presently you're likely idling on the power circuit and with a low vacuum your power valve could be opening.
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Old 04-30-2014, 08:37 PM   #3
67 chevelle
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Re: Too Rich: SBC 670 Holley Street Avenger

make sure your choke is not stuck closed
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Old 05-01-2014, 09:36 AM   #4
msgdsrf
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Re: Too Rich: SBC 670 Holley Street Avenger

Both good suggestions. Your vacuum definately should be higher with that setup, idle in gear with say around 14". What is your idle speed?
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Old 05-01-2014, 01:10 PM   #5
c10seth
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Re: Too Rich: SBC 670 Holley Street Avenger

Quote:
Originally Posted by geezer#99 View Post
Hook your vac advance up to manifold vacuum, your idle and vacuum will come up, turn down your idle and adjust your mixture screws. Presently you're likely idling on the power circuit and with a low vacuum your power valve could be opening.
I will give this a shot. Thank you much.

Quote:
Originally Posted by 67 chevelle View Post
make sure your choke is not stuck closed
Electric choke seems to be opening and closing fine, but I'll keep a close eye on it.

Quote:
Originally Posted by msgdsrf View Post
Both good suggestions. Your vacuum definately should be higher with that setup, idle in gear with say around 14". What is your idle speed?
idle speed was between 500 and 900rpm. I had to adjust the curb idle to keep it from stalling. I'll reconnect the vac. advance and go from there.

Thank you all,

c10seth
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Old 05-09-2014, 07:14 AM   #6
c10seth
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Re: Too Rich: SBC 670 Holley Street Avenger

Hey, all.

I reconnected the vacuum line for the dizzy advance, threw in a new set of plugs, and wow. That made a huge difference. I was getting about 20inHg and she stopped belching black smoke. I didn't realize that was that big of a deal with this Holley 670. Thank you for your help ^_^

Seth
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Old 05-09-2014, 09:47 AM   #7
67 chevelle
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Re: Too Rich: SBC 670 Holley Street Avenger

Funny it turns out to be a distributor issue , when all indications would point towards the carb
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67 Small window , 7 foot bed , tweaked 6.0 LSX 2004R Medium Olive
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69 Long Fleet , Custom , 6.0, 4l60 , AC , Medium Olive
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