Edelbrock 1406 & 1411 Installation Summary
Note: My final and best solution on the carb installation is presented here however you can see the history of the different things I tried by Clicking Here
Note 2: I had briefly installed a 1406 600cfm on my 1964 429 and it also ran fine out of the box and is an easier bolt and go application as you don't have to worry about the larger rear primaries found on the 1411 750 cfm carb. It 1406 cfm is also much more in line with the factory CFM rating but for those with a hot round heart and perhaps with a rebuilt engine and ready for more HP the 750 can give you more umph!
For more specs and info on the original carbs check out this Help Page --> Carburetors used in 1963 & 1964
From the factory a heat riser is closed during cold startup forcing exhaust gases across a center channel in the intake with an internal choke tube causing the engine to heat up faster, improving air/fuel mixing, and heating air drawn into the heat tube from the bottom of the intake causing the carb to go off choke as the engine heats up. The aftermarket Edelbrocks, with it's electric choke, does not use the internal choke tube, and does not need the 300+ degree heat under the carbs base. In addition it has been my experience that even if the heat riser butter fly is removed there is still 300 degree temps at the center of intake from bypass gases and can potentially cause vapor lock under certain condition. It has been my experience that completely removing the exhaust gas heat from the intake provides the best condition for optimal performance of the Edelbrock carbs.
Below are 3 easy steps to eliminate the exhaust heat form the equation:
1) Remove butterfly from heat riser, or install spacer, or remove heat riser spring and wire or weld open, or install new exhaust pipe eliminating heat riser. The factory heat riser is closed during cold set-up. Since step 2 below blocks the exhaust channel across the intake, the left side exhaust would not have anywhere to exit until engine heats up causing tremendous heat and back pressure potentially causing catastrophic engine failure.
(see picture 1 below)
2) Place blocker plates at center exhaust port between cylinder head and intake manifold. I used thick galvanized roofing steel with the thicker intake gaskets sets (not the metallic gaskets). NOTE: I recall someone saying there are exhaust gaskets available with block plates included but my searches have come up empty.
(See picture 2 below)
3) Replace original intake to carb spacer with PCV nipple with 3/8" insulator spacer. I used a Trans-Dapt TRD-2446, however, there are other brands on the market. 3/8" seems ideal height, especially if you want to use the stock air cleaner and the adaptor sold by Russ Austin. If you are running an aftermarket air cleaner and have additional height clearance to hood, you might consider a taller spacer for even better air/fuel mixing and dispersion.
(See picture 3 below)
NOTE: You do not need to remove the internal choke tube, or block choke tube ports at end, or the top of intake channel ports if you do steps 1 and 2 above. In my Carb project I started by trying to block the intake at the 2 top channel ports and the 2 ends of the internal choke. If you stop the flow of exhaust gas at the cylinder head to intake, you do not have to worry about anything else. This would be useful if your internal choke tube is intact and solid and might want to reuse the intake manifold in a stock application later on.
Electric Choke Wiring
You need a 12 volt switched source. For 1964 Cadillacs with the Tubo Hydramatic you can simply tap into the pink wire that goes to the kick down switch at back of carb. For all 1963's and 1964 with the Hydramatic you will need to run a wire into the car and behind the dash to tap into the pink ignition wire.
TV Rod Connection (all 1963's and 1964's with Hydramatic transmission)
You will need to adapt a plate to the Edelbrock throttle plate to connect the TV rod from the transmission. This helps control shifting on the Hydramatics and is not optional. The TV rod plate from a Carter AFB can be modified to attach to the Edelbrock. Others have posted information on the Website
Transmission Kick-down Switch (1964's with the Turbo Hydramatic)
The 64's with the THM transmission had a kick-down switch mounted to the left rear of the factory Carter AFB and Rochester 4GC. The Edelbrocks do not have a mounting block on the carb for the switch and you will need to adapt a switch to the carb and accelerator linkage in order to provide the kick-down function while using the Edelbrock. NOTE: I have ran my 1964 Coupe de Ville with the Edelbrock for 10+ years without a kickdown switch with no issues. the big 750 cfm coupled with Pertronix ignition has provided me plenty of power to get up and go when I need to pass with out that feature. IT IS on my to do list but has not been pressing and definitely consider that an optional item.
Air Cleaner Housing - Using Stock Air Cleaner (see picture 4 below)
Since the top of the Edelbrock is 5 1/8” wide and the original air cleaner housing neck is about 4 3/16” to fit the Rochester 4GC or Carter AFB you will need some sort of adaptor to use the original air cleaner. Russ Austin sells a never nice high quality adaptor that raises the air cleaner 1 3/16”... which just clears the hood if using a 3/8” intake to carb spacer. If you go any higher the air cleaner will probably hit to hood.
Porting Intake Manifold for 750cfm Edelbrock 1411 (see picture 5 below)
The front primaries on the stock intake are considerably smaller than the venturi and butterflies on the Edelbrock 1411 and performance can be gained by porting the front intake primaries to match the Edelbrock. My local machine ship ported mine which can be see in picture 3 below.
NOTE: The 1411 will not bolt directly to the stock intake as the front butterflies will hit. You would not want to do this anyway since you want to use some type of insulator spacer to replace the factory spacer as noted previously.
Fine Tuning the Carb using Calibration Kits (see picture 6 below)
Performance can often be tweaked by changing out the jets, metering rods and/or step-up springs. You can get calibration kits from Edelbrock that has an assortment of metering rods, jets, and step-up springs.
- The kit for the Edelbrock 1406 600cfm carb is the 1487 kit.
- The kit for the Edelbrock 1411 750cfm carb is the 1489 kit.
I ran my 1411 on my 1964 CDV for at least 5 years without changing anything. I later did some experimenting and ended up running my carb a bit richer using different metering rods only which was a very simple mod. I ended up going with the .073 x .042 for 4% richer mixture on both cruise and power mode.
The Bottom Line is I consider rejetting optional. Get everything running like you want it as set up out of the box and then if you like purchase a Calibration Kit and take baby steps to run leaner then richer, and try changing out the step-up springs. The Edelbrock owners manual has great info on how changing these out the jets, rods, springs may affect performance and includes nice charts to see exactly how these changes will affect the carb specs. It also goes into detail regarding other aspects of when you might consider recalibration such as using a longer than stock duration cam.
(Picture 2: Plate to block center exhaust port)
I am using a Spectrum air cleaner —which is a K & N clone only a bit less expensive than the K&N
You can get it with a blue filter material that looks good with the stock engine blue coloration
It is a 3 inch air filter material that is very much superior to the chrome one inch Cal Custom air filter I had on the carb prior to this
I know the carb is pulling the correct air volume it SB with this set up now
I know the air flow was restricted by the one inch Cal Custom prior air filter
Pls change Spectrum ( my tv provider ) for the Specta air filter that I have on my 64 — thanks
It has been a while
I'm acquiring all of the parts needed to install a 1406 and have two quick questions.
First, which gaskets are used with the Trans-Dapt TRD-2446 spacer? I assume you want ones that match the spacer as closely as possible.
Second, when installing the shims to block the center exhaust port, do you put the intake manifold gaskets over the shims and torque everything down? The extra thickness of the shims seems to make things a little uneven. I have ordered the thicker material gaskets as you mentioned. Will these allow everything to seal?
- I used the gaskets that cam with the 1406 and spacer. I don't recall having to buy any extra gaskets.
- I put gasket on top of metal plate. Note I used the thick intake gasket ... not the thin metal ones. Mine has been sealed for 10+ years with the thick gasket.
Thanks, Jason. I have ordered a set of Best gaskets #14046 E They are made from the thick material.
is there a carb switch out for the 63 390? and what would be the complications
Edelbrock 1406 is a good replacement with minimum mod/issues. Scroll up and read the initial post.
Because the trans shifts off the TV rod in the 63 —attached to the carb I would rebuild the carb you have or get another stock rebuilt carb If needed
You will have to make— your own bracket for the TV rod if you go with an Edelbrock replacement carb
I think the trans shifting is not an issue I choose to be playing around with
I do think the stock Carter cab is a superior carb but I do not know if some 63 390’s came with that carb stock
ok,,thanks i was curious,