Edl-1411: backfiring

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Jan 5, 2005 | 08:42 PM

Steve A

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From: So.Cal

Edl-1411: backfiring

Well, I seem to be getting my 390 dialed in, it's just taking a lot of time and cuh-ching ($).
I'm running a new EDL-1411.
My current problem seems to be backfiring at WOT, at higher rpm's.
I don't have an onboard tach, so, I don't know what the rpms are when it starts backfiring, but, it's at the mid to upper end of the powerband. After it comes on the cam and the secondaries open. Say, around 60-to-70 mph in 4th gear, with WOT.
If I back off the throttle and allow the secondaries to close, it seems to smoothen out again.
Timing is set at 10' BTDC, w/new dissy, coil and ignition module.
My impression is that the secondaries are too rich. How would I correct that ?
steve

Jan 6, 2005 | 02:49 AM

Ford_Six

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From: The Big, Oregon

Out the exhaust or intake?

Jan 6, 2005 | 09:52 AM

Steve A

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From: So.Cal

Out the exhaust.
I seem to have cured the intake backfireing.

Jan 7, 2005 | 08:41 PM

Steve A

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From: So.Cal

Okay, after some discussion with the counter man down at my local Kragen, I changed the vacuum advance line and the power brake hose. Just on GP.
While changing out the brake hose, I noticed some frayed wires that lead to the dissy. After untapeing a few inches of wiring harness I saw that a few of the wires had cracked insulation. So, I cut them back and crimp connected them back together.
Now, it seems that most of the back-firing is gone.
Don't know if the problem was a vacuum leak or if it had to do with the wires.But now...,
at the same point where it used to back fire, it boggs instead.
It seems that as soon as the secondaries open, it starts bogging down.
If I lift my foot and let the secondaries close, it picks up power, or at least that's what it feels like.
Is that too much fuel or too little fuel ?
I'm a newbie to Edelbrocks, I don't know where to begin checking or what to adjust.
Any ideas ?
steve

Jan 8, 2005 | 12:38 AM

LxMan1

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From: Louisville,Ky.

Check the spark plugs and see how they look. Black too rich, white too lean?

Jan 9, 2005 | 07:00 PM

Steve A

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From: So.Cal

Just checked them, very clean.
New set of plugs as of a few days ago, with a few hundred miles on them and they look real good. Not too black or too white.
Oh, btw, while it was parked, I put a tach on it and took the rpms up to 4000, then opened it up (wot). It was at 5000 that it started to bog. Made a fluttering sound.

steve