Edelbrock 1406 Nightmare

[Heavy Metal]

Hello Friends,

I'm looking for help on tuning my Edelbrock 1406 carb. I can't get the tune correct. I still have a heavy bog with hard acceleration.
302 C4 Weiland Intake, 20 lbs vacuum at idel, idel screws out 1 1/2 turns.
Sometimes I stall out just getting out of my garage. I installed a fuel regulator and running 5lbs pressure. I bought the kit with all the rods, springs, jets.
I've been all over the map with Idle timing, jets up/down, metering rods up/down, springs up/down, squirters up/down, pump rod all holes. I'm ready to throw this thing in the trash. I have more than 40hrs trouble shooting this thing. I went back to stock settings and still same problem.
Any advise would be greatly appreciated. Thank you.
Heavy Metal
Florence, SC

 

[giantpune]

Do you have any way to check AFR with an O2 sensor? That makes it easy mode seeing exactly what the carb needs. Also, proper adjustment of the plates for the transfer slots.

Its not all carb, though. Ignition matters just as much. Like if you have the timing off or vacuum advance hooked up wrong.

 

[73inNH]

Do you have any way to check AFR with an O2 sensor? That makes it easy mode seeing exactly what the carb needs. Also, proper adjustment of the plates for the transfer slots.

Its not all carb, though. Ignition matters just as much. Like if you have the timing off or vacuum advance hooked up wrong.

Agreed. I installed a clamp-on O2 sensor in my exhaust and I can monitor AFR while tuning. When done I simply remove it. It makes tuning much easier.

For what it's worth, I had to go up several squirter sizes on my Edelbrock. There was a kit with a couple of different sizes, I would reset the carb to stock then go right to the biggest squirter.

From there, see if you can get your carburetor right without engaging the secondary. Meaning part throttle, does the carb work well at stock settings with the enlarged squirters.

I recommend tying open the choke as well. While the choke is nice to have, it's not necessary, and if it is causing a problem tying it open will at least eliminate that possibility.

At the end of my tuning, I did end up with richer rods and jets in the primary and secondary. But the squirter upgrade made the largest difference.

For the moment, tie off the choke, upgrade the squirters and stay out of the secondaries. See how it runs.

They could be all kinds of other factors in play as well, including air leaks and timing, etc.

Just my $0.02.

Note: you can also drill out the squirters with a pin vice, but buying the edelbrock kit is easier.

 

[Heavy Metal]

Thank you for your suggestions.
My Elec. choke it leaned out all the way, so when warm the plate is wide open. so no issue there.
My timing is currently 18* BTDC and ive been all over the range of 15* to 22* with little success.
I feel like its in the squirter and will try the fattest Nozzle which is 0.043". I do have the nozzle kit.
and currently running stock 0.031". But im associating the bog with too much fuel, my opinion.
I look forward to more suggestions and thanks again.

 

[73inNH]

Got it. Try the carb with stock setting and the fattest squirter. Let us know.

Don't get into the secondaries when testing. Just see if it runs well enough to drive at normal speeds.

Good luck!

 

[Bentworker]

Thank you for your suggestions.
My Elec. choke it leaned out all the way, so when warm the plate is wide open. so no issue there.
My timing is currently 18* BTDC and ive been all over the range of 15* to 22* with little success.
I feel like its in the squirter and will try the fattest Nozzle which is 0.043". I do have the nozzle kit.
and currently running stock 0.031". But im associating the bog with too much fuel, my opinion.
I look forward to more suggestions and thanks again.

18 degrees initial? That seems like a lot. What is all in timing?

Like others have suggested an AFR gauge will make things much easier.

 

[Steve McMahan]

I think the comments on the squirted are not nozzle size related as volume of the squirted diaphragm. On my 351 Ranchero, I went to the largest volume accelerator pump and that eliminated my off idle stumble. Just my 2cents.

 

[RIBS]

Did you clean rebuild entire carb, adjust floats, etc? Check for vacuum leaks? Did it ever work right? If so, what changed?

 

[Precision Transmission]

Have you bought and thoroughly read the book on these carburetors?

 

[Heavy Metal]

Hello,
And thanks again for your responses.
The carb is new and was fat out of the box.
I have read the owener's manual extensively, watched all the Youtube videos, read all the forums.
I think my next move will be float height and fuel pressure. Maybe my fuel pressure gage on my regulator isn't accurate, Ill try 4lbs and using a 1/2" drill bit and 1' drop on the floats.

 

[Sheriff41]

You might try Edelbrock's Tech Support Line: 800-416-8628. I'm sure they want you to be satisfied with your carb.

 

[Bobby]

I had a 1406 on my 72. Ran great until it didn’t. Bought a new one but not much better. After my stroker build, I purchased a 1411 750 CFM. Ran great till it didn’t. I stopped cheaping out and got a Holley Sniper and a dual sync distributor. Now I’m happy because my Stang starts and runs reliably all the time. Anyway, the Sniper will always run great on 93 pump gas……the carbs will run better and last longer on sugar free gas (ethanol free). The better way to run a carb is to install an electric fuel pump and a pressure regulator.