Ok over the weekend i was doing some work on my 86 because i thought i was having valve tap or what i thought was a valve and piston colliding. But it turned out to be loose rocker arms ( vibrate themselves loose a little). So over this 2 day long teardown to the lifter valley i inspected each lifter and found no signs of odd wear or mishaping and put everything back together and figured out i just had some rockers that had become loose ( phew thank God no valve slapping) but now im having backfire from the carb when i smack the pedal to floor quickly. i drove it around and even mid throtlle never showed any problem so i assume this is a secondaries issue. one thing i noticed is that it never did this before and nothing was differetn when i put it back together EXCEPT i noticed when i had the carb off and was looking over it i noticed the secondaries barely openedwhen i pulled the throttle linkage all the way open ( because of some little moving bracket that has to do with the choke rod assembly) was keeping them from opening . now i have it fixed so they can open and i assume thats why it wasnt backfiring before cuz it wasnt able to make a lean mixture (that i assume its doing now) without those flaps opening wide. My question is how do you richen secondaries on these edelbrock carbs (#1406 electric choke). if you need more info just let me know. Thanks guys for the help!!

 

There are some links in one of the carb stickies to the edelbrock tech site and all the instructions and tear downs on the carbs.

Edit: Found:

http://www.edelbrock.com/automotive_...406_manual.pdf

And a video:

http://www.edelbrock.com/automotive_...ech_vids.shtml

 

The secondaries aren't supposed to open unless the choke is fully opened.

I'm not sure what you did to what, but I suspect you defeated the air valves that prevent the carb going lean when going WOT.

 

Nah.. my electric choke housing is broken so the choke isnt functioning properly and theres this little bracket behind where the tranny valve cable hooked up that when you pull throttle wide open it would come all the way back but it held the secondaries closed.. looks like a saftey feature for when an engines still cold that bracket keeps the secondaries from opening if you floor it so the carbs doesnt create fireworks.. did also realize my fuel line came undone at some point in the disassembling and moving it around and was pouring pretty bad.. hooked it up tightened it down and so far it hasnt done anything.. ive stomped it a couple of times in park and no pops so far.. guess it wasnt leaking more than it was getting.

 

It could be a number of things. Number one check you timing make sure you are not to rich. Also it could be a bent or damaged lifter.

Is your carb vacuum or mech secondary. If its vacuum I believe you can adjust the spring strength. If its Mechanical make sure you have even flow throughout full throttle accel and check your power valves as well as your jets they could be loose. Check your float levels as well.