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-   -   ping ping ping edelbrock 1406 (https://67-72chevytrucks.com/vboard/showthread.php?t=214486)

67chevemall 10-27-2006 01:15 PM

ping ping ping edelbrock 1406
 
Hello

I just put a new carb on my truck and it pings like crazy
I guess I have to adjust it but where to start?
Could this be timing? Should I turn the dizzy?

Any help would be great!

Cheers

RSRXION 10-27-2006 02:09 PM

Re: ping ping ping edelbrock 1406
 
Detonation is most likely a direct result of too much advanced timing. Also known as spark knock or pinging it can also be caused by extreme heat during heavy towing operations , low grade fuel or summer driving conditions.

Detonation is sometimes accompanied by a couple of other undesirable behaviors like difficulty starting the engine when it's warm and engine run on after the key is shut off. These behaviors are not always present in an advanced timing situation but they are good indicators of the cause.

Fix the problem as soon as you can. Detonation is murder to the valvetrain of any engine and will surely do harm. The valve seats will be the most likely victim but valve stem/head failure or piston damage will follow closely behind. I don't need to tell you what will happen if you drop a valve head or burn a piston. It's nearly always a bad sign when small parts of metal start bouncing around inside your engine.

Good luck, Dean

RicksTrucks 10-27-2006 02:30 PM

Re: ping ping ping edelbrock 1406
 
I have a similar problem after having a 1406 installed and my HEI worked on. It has been doing the 'octane ping' upon acceleration. Just the last day or two I am now getting back firing while going down the road. It will hesitate, then hear a pop in the exhaust. Not to hijack, but maybe this will help.

I am going to try resetting the timing and see what happens.

67chevemall 10-27-2006 03:47 PM

Re: ping ping ping edelbrock 1406
 
Yep I think my timing is out. Nothing I do to the carb adj's changing the ping
ping ping pop.

I'll try turning the dizzy I've never used my timing gun maybe now is a good time too.

Werewolf 10-27-2006 03:50 PM

Re: ping ping ping edelbrock 1406
 
Maybe the old carb was dumping more fuel into the engine, creating a richer condition in which you could run more timing, but the new carb is leaned out, and the timing is set high. Just a guess. In any event, dropping back the timing should help. If you end up bringing it below stock specs, though, there's likely another problem.

A.P. 10-27-2006 04:52 PM

Re: ping ping ping edelbrock 1406
 
I had a similar problem, and it turn out that it was a lean condition. At the edelbrock site there are some tech videos that are very helpfull. Here is the site. Scroll down the page and click on 1 thru 6 or the one that best discribes your problem. Good luck. A.P.
http://www.edelbrock.com/automotive_...ech_vids.shtml

Green Machine 10-27-2006 05:46 PM

Re: ping ping ping edelbrock 1406
 
I am wondering if the vacuum advance was hooked up to ported vacuum or a non working port before. If it is now hooked to a full manifold vacuum port, it may be giving more advance at low speeds than before.

lilpup69chevy 10-27-2006 05:51 PM

Re: ping ping ping edelbrock 1406
 
thats what i was thinking i figure they may have had it set where it stays advanced at all times the edelbrock carbs have two different vaccuum ports one is full time and one operates part time i'd guess you'd say i guess one way to see if its that or not is to unhook the vacuum advance and see if it still does it

RSRXION 10-27-2006 05:51 PM

Re: ping ping ping edelbrock 1406
 
Excellent point Green !

clay68c10 10-27-2006 05:57 PM

Re: ping ping ping edelbrock 1406
 
I think edelbrock jets their carbs a little lean, that's probably part of your pinging. My 1411 was lean out of the box. Not a problem but I got more power out of it when I richened it up. It helps if you have the jet/rod/spring calibration kit. They are easy to tune.

jooooooe 10-27-2006 10:36 PM

Re: ping ping ping edelbrock 1406
 
the problem with the edelbrock is that it is toooooo adjustable, I used one once, first it was causing a lean misfire on the top end (at WOT under load the engine would start popping back through the carb around 4200 rpms), went through dozens of springs and jets, eventually I got it right. the symptoms associated with lean firing conditions (whether at WOT or at part throttle) can be easily mistaken for ignition problems.

jamon8 10-28-2006 11:25 AM

Re: ping ping ping edelbrock 1406
 
the trick is to not buy this carb if you have higher than 8.5:1

and if you have a bigger than 420 lift cam

and if you have anything but stock heads

incoma 10-28-2006 12:17 PM

Re: ping ping ping edelbrock 1406
 
Quote:

Originally Posted by jamon8 (Post 1847594)
the trick is to not buy this carb if you have higher than 8.5:1

and if you have a bigger than 420 lift cam

and if you have anything but stock heads


I agree. I used to run a 1406 with a stock 350 engine and T350 tranny. I got 17mpg with that combo. Now with a 1406 on a 350 with edelbrock cam, and 200 4R trans I'm getting 14 mpg. I thought matching edelbrock parts with edelbrock parts would be the right thing to do, but I now think differently.

I also agree that these carbs are too adjustable. Finding the right combination of jets, rods, etc can take quite a bit of time. However, for a novice at carbs such as myself, I can actually understand how to adjust it, and I can even follow edelbrock's instructions. From that standpoint its a good product.

Now back to the post - I'd throw a timing light on it and see what your timing is. Be sure to remove the vacuum advance line from the carb when you do this. Also plug up the carb port, otherwise you're engine won't be running correctly when you check the timing. If timing isn't it, your carb is probably running too lean. Just my .02.

67chevemall 10-28-2006 12:53 PM

Re: ping ping ping edelbrock 1406
 
Thanks guys I'm almost to nervous to run it to check the timing. All I need is engine damage. I have to give it a try though.
I'm trying to get everything together before I start it.
My vaccum line is to short to reach to other vacc. port on the carb.
I have it on the left one now because it reaches there, but the install manual says I should have check the hose while running to see if there was vaccum or not.
I think I should get the vaccum hose on the right port first but I'm not sure which one to use.
Then I'll get out the timing gun and turn the dizzy till it stops pinging
Then I'll tune the carb.
??

Werewolf 10-29-2006 07:54 PM

Re: ping ping ping edelbrock 1406
 
Don't panic over the ping. If it's loud and harsh, yeah, it's a big problem, and if you let it go on for a long time, it can be a problem.

OTOH I've got a '92 Caprice that has pinged (light to heavy) since the day I got it. I've gone through everything trying to figure *that* out, but was never able to, so I finally gave up. Car's got 480k on the stock drivetrain. The pinging isn't killing this engine. :)

Boog 10-29-2006 09:13 PM

Re: ping ping ping edelbrock 1406
 
Quote:

Originally Posted by 67chevemall (Post 1847649)
Thanks guys I'm almost to nervous to run it to check the timing. All I need is engine damage. I have to give it a try though.
I'm trying to get everything together before I start it.
My vaccum line is to short to reach to other vacc. port on the carb.
I have it on the left one now because it reaches there, but the install manual says I should have check the hose while running to see if there was vaccum or not.
I think I should get the vaccum hose on the right port first but I'm not sure which one to use.
Then I'll get out the timing gun and turn the dizzy till it stops pinging
Then I'll tune the carb.
??

You should check the timing with the vacumn hose disconnected from the dist and plugged. While engine is running unplug the line and see if it has vacumn on it, if no vacumn at idle it is ported vacumn. If it has vacumn at idle it is full time manifold vacumn. Many discussions over the years on which is best. Try it both ways and see how your engine performs.


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