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Topic: backfiring with Edelbrock carb and intake...ideas?

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Re: backfiring with Edelbrock carb and intake...ideas? (5/15)
 3/13/12 4:57pm
VikingVette
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Greer, SC - USA

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Thank you CT..I will pass that along.  The mechanic is also replace the valve covers at this time, so he can easily check that as well!

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Warning: The surgeon general has declared that it is NOT unhealthy to smoke your competition AND I just discovered that my corvette is a hybred.  It burns gas and rubber! 
Re: backfiring with Edelbrock carb and intake...ideas? (6/15)
 3/13/12 6:09pm
DaveMLifetime Member
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Flanders, NJ - USA

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I never had any problem with backfiring with my ZZ4. Good luck with it, I hope they get it worked out for you.
Dave


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Re: backfiring with Edelbrock carb and intake...ideas? (7/15)
 3/14/12 11:50am
philip
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I never had any problems with my ZZ4 with an Edelbrock carb. Ran fine and had plenty of power. Actually had more power than with the Holley 750 that was on it originally. If the tech can not find the cause of the backfire maybe it is time for a new tech. I know of mechanics with lots of years of experience that can not do any more than change parts until the problem goes away.

The backfiring occurs when you are slowing and pull the trans into a lower gear. This will cause a rich condition and there is a hot spot in your exhaust that is igniting the fuel in the pipes/mufflers. Usually there is not enough oxygen in the exhaust system to promote burning so look for an exhaust leak allowing O2 to enter the pipes.
Re: backfiring with Edelbrock carb and intake...ideas? (8/15)
 3/14/12 12:27pm
Adams' AppleLifetime Member
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philip said: The backfiring occurs when you are slowing and pull the trans into a lower gear. This will cause a rich condition and there is a hot spot in your exhaust that is igniting the fuel in the pipes/mufflers. Usually there is not enough oxygen in the exhaust system to promote burning so look for an exhaust leak allowing O2 to enter the pipes.

With the complete description of the problem now, I agree with Phillip...you prolly have an exhaust leak, most likely somewhere up around the junction where the pipe meets the manifold. If you still have the AIR system on the car, check all of that, too...a leak in the tubes, or a bad diverter valve can also add more O2 to the exhaust stream, and cause a backfire on decell...



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Re: backfiring with Edelbrock carb and intake...ideas? (9/15)
 3/14/12 12:29pm
VikingVette
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Thanks Philip.  That was good information.  I had wondered why the popping was way back by the mufflers.  That is probably where the 'hot spot' is.  This mechanic did tell me that he would check the exhaust system for leaks.  I was also VERY pleased to read that you have had GOOD luck with an Edelbrock vs the Holley.  That gives me hope.  Again, you ARE right about your assement about mechanincs.  I have HAD (past tense) one of those too.  He was VERY good at re-building engines though!

______________
Warning: The surgeon general has declared that it is NOT unhealthy to smoke your competition AND I just discovered that my corvette is a hybred.  It burns gas and rubber! 
Re: backfiring with Edelbrock carb and intake...ideas? (10/15)
 3/14/12 12:33pm
VikingVette
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Greer, SC - USA

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Posts: 264

Adam,
I have always had a problem with one of the header bolts.....right now I can hear a ticking at idle and I know that one header (hooker headers) bolts is not as tight and the ticking is exhaust (I think).  I do appreciate all the input that I have received. 


______________
Warning: The surgeon general has declared that it is NOT unhealthy to smoke your competition AND I just discovered that my corvette is a hybred.  It burns gas and rubber! 
Re: backfiring with Edelbrock carb and intake...ideas? (11/15)
 3/14/12 12:58pm
DaveMLifetime Member
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Flanders, NJ - USA

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I have Hooker Headers (side pipes) and I'm always tightening the header bolts, I check them every couple months and there is always one or two that have loosened up.

Dave


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Re: backfiring with Edelbrock carb and intake...ideas? (12/15)
 3/14/12 5:57pm
Jaws79Lifetime Member
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I remember they used to have have some header bolts that had a locking piece to keep them from coming loose, but I don't know if they're still around
 
Barry
 
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Re: backfiring with Edelbrock carb and intake...ideas? (13/15)
 3/14/12 7:07pm
danascar
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You can get locking bolts at Summit....http://www.summitracing.com/parts/STG-8911A/

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Re: backfiring with Edelbrock carb and intake...ideas? (14/15)
 3/14/12 10:28pm
DaveMLifetime Member
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Flanders, NJ - USA

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1982 Black, ZZ4, Hooker Side Pipes, 3.55 Rear, Rebuilt & upgraded 700R4, All new suspension, brakes, & new Charcoal interior.


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Posts: 2552

I looked into those Dan, I don't have any room beyond the head of the bolt.

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Re: backfiring with Edelbrock carb and intake...ideas? (15/15)
 3/15/12 12:14pm
philip
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Marana, AZ - USA

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The stage 8 bolts have another nice feature besides the locking ring, they have an Allen and a hex head. Fot the areas that it is hard to get a box wrench on the Allen wrench will fit.

http://s80.photobucket.com/albums/j199/64elcamino/77%20Nova%20project/exhaust/?action=view¤t=P1010002.jpg
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