Edelbrock carb question

[rockyrivermark]

I have an edelbrock 1406 which is a 600cfm with electric choke.

I got it dial in pretty good but want to test out a smaller and larger nozzles

I’m guessing the carb has to be removed to do this safely? Looks like I have to remove the top section of the carb to access it?
Thanks for any info provided.
Mark

[Steeveedee]

Piece of cake. You only have to remove the air horn to change out the jets. But if you bought the tuning kit, you may only have to remove the little plates that hold the metering rods and springs down, and then change them out.

[rockyrivermark]

Originally Posted by Steeveedee

Piece of cake. You only have to remove the air horn to change out the jets. But if you bought the tuning kit, you may only have to remove the little plates that hold the metering rods and springs down, and then change them out.

I have already changed the metering rods and springs.
What I’m tweaking now is the accelerator pump nozzles located under the choke butterfly.
I think the top half of the carb has to come off to access the screws?
And guessing too risky to do with the carb on the car even with shop towel blocking from a screw being dropped in.

['68OrangeSunshine]

It might be easier to do an accelerator nozzle change on a bench, but if you're careful, you don't really need to pull the whole carb off the engine.

[Steeveedee]

Get some of those super-strong magnets and put them on some steel rods. They'll catch the screws if you drop them. I have these extra-large mitts that make me use expedients like those magnets. Now that uncle Arthur Itis is settling in for a lifetime stay in various parts of my body, I find myself using more of that sort of thing. Of course, a replacement base gasket is cheap enough, too.

[pjmoreland]

Here's a photo that shows the top section removed. I've removed the top section numerous times with the carb still on the engine. The most challenging part for me has been the two tiny clips that are on the accelerator pump and choke linkages.

[custom10nut]

Suggestion:
Look up Thompson Performance LLC in California.
They make Brass “Power Blast Plates” for Holley and Edelbrock Carbs.
They take about 10 minutes to install
It is a plate for the fuel to atomize more, for a better Air Fuel mixture.
I used to have the “ hesitation off the line” issue with my truck, until I put this plate in.
Now, there’s no hesitation at all

[geezer#99]

I’ve encountered those before.
Worked great.
Better than searching for the perfect squirter size.

https://thompsonperformance.com/

[72SB]

Mark

Are you looking for more power, fuel efficiency or feel you have a pump issue?

IMHO it's best to remove carb and just do it on bench unless it's just metering rods and step up springs. Bending over fender and changing small parts inside carb....you don't want to drop anything inside it while on the motor.

My go to carb for SBC and SBF is the 1406. Edelbrock makes a specific kit, # 1487, specific to the 1406 carb. It has a variety of jets, metering rods and step up springs and a grid indicating what combo of each to make changes. My need was when I went from a stock 327 to a head/cam 355 crate motor making over 400hp.

You really need to have timing nailed before making internal carb changes. Controlling vacuum advance in terms of how much and when it comes in and stops. Crane used to make an adjustable VA and a detent plate kit to do this but no longer available. Homemade alternates for the detent plate have been done.

Pic of the Crane VA with detent plate installed to limit anount of timing advance it provides. Ideally you want 24 degrees of timing at idle with VA so 10-12 degrees base (no VA) and 10-12 of VA when connected and generally 35-36 degrees all in 2500-3k rpm.

[68 P.O.S.]

Why are you changing the accelerator pump nozzles? The 3 different built-in adjustable settings weren't getting the job done? Probably need the .043 squirter.

Is the accelerator pump plunger in good shape and working proplerly?

[OregonNed]

Originally Posted by custom10nut

Suggestion:
Look up Thompson Performance LLC in California.
They make Brass “Power Blast Plates” for Holley and Edelbrock Carbs.
They take about 10 minutes to install
It is a plate for the fuel to atomize more, for a better Air Fuel mixture.
I used to have the “ hesitation off the line” issue with my truck, until I put this plate in.
Now, there’s no hesitation at all

Same experience!

[rockyrivermark]

Everything else is dialed in. Timing etc. just seeing if there is some HP I’m leaving in the table.
Thanks for all the replies.
I got what I needed.
Mark

[72SB]

Originally Posted by rockyrivermark

. Timing etc. just seeing if there is some HP I’m leaving in the table.

Mark

Than you would want this carb kit and focus on the upper right quadrant. Take baby steps, drive, repeat if needed.

https://www.summitracing.com/parts/e...mber+Ad+Groups

[nightrider388]

Good luck on getting the jets out of the bottom of carb. They are soft and can be really hard to get on while leaning over the engine bay.

[rockyrivermark]

Originally Posted by nightrider388

Good luck on getting the jets out of the bottom of carb. They are soft and can be really hard to get on while leaning over the engine bay.

I’m not removing jets. I’m changing accelerator pump nozzles.

['68OrangeSunshine]

Be advised, the little brass parts are not magnetic, so a retrieval magnet is useless there.

[Steeveedee]

Originally Posted by '68OrangeSunshine

Be advised, the little brass parts are not magnetic, so a retrieval magnet is useless there.

I'm recalling that the metering rods are brass, but it's a bit tough for them to accidentally get dropped down past the throttle plates. Same for jets. FWIW, I had a 1406 on a 305 Chevy and only had to go 4 numbers up on the metering jets to cover an off-idle stumble. Off the shelf, it may have worked OK, but the headers may have scavenged just enough...

When I go the gun range, I always think that a brass magnet would be a good thing. Too bad such a thing doesn't exist.

['68OrangeSunshine]

Originally Posted by Steeveedee

I'm recalling that the metering rods are brass, but it's a bit tough for them to accidentally get dropped down past the throttle plates. Same for jets. FWIW, I had a 1406 on a 305 Chevy and only had to go 4 numbers up on the metering jets to cover an off-idle stumble. Off the shelf, it may have worked OK, but the headers may have scavenged just enough...

When I go the gun range, I always think that a brass magnet would be a good thing. Too bad such a thing doesn't exist.

Lead magnets would be good too, sifting thru the butts. Or aluminum magnets, when collecting beer cans.

[Steeveedee]

Originally Posted by '68OrangeSunshine

Lead magnets would be good too, sifting thru the butts. Or aluminum magnets, when collecting beer cans.

Wouldn't that be great? Get your helicopter and fly over any SoCal beach with the aluminum magnet turned on? It would actually pay for maintenance on the whirlybird. Especially if it picked up non-empty cans, up to a limit.