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 1: Butterfly removed from stock heat riser)
(Picture 2: Plate to block center exhaust port)
(Picture 3: Trans-Dapt TRD-2446 Intake to Edelbrock Carb Spacer - Insulator)
(Picture 4: Edelbrock Carb to Air Cleaner Housing Adaptor from Russ Austin)
(Picture 5: Front primaries ported/enlarged for Edelbrock 1411)
(Picture 6: Calibration Kit for the 1411 Carb. Includes metering rods, jets, step-up springs)
If you have a 63 390 with the transmission rod that shifts the trans -on the carb
If it was my own car --i would stay with that carb and have it rebuilt --due to you otherwise having to adopt a plate for the Edelbrock to work the trans correctly --if you are capable of doing that fine
Car in my family from day one -off the showroom floor
I have had both the AC idle up and the kick down switch on the stock carb disconnected for many years
Both of which are not necessary in my own opinion and making the change to the Edelbrock an easy change for most regarding these two carb add ons
The 429 behind the TH400 will just about pass anything at any speed without the kick down ( passing gear )
Seems it is always --kicking the passing gear that has damaged most automatic transmissions i have managed to break ( not saying the Th400 will break doing that )
Just the down side of being hard on our cars
The driveshaft will always be the weak link in the drivetrain as i see it ( those U joints )
( Carter on 64 429 -to Edelbrock 1406 electric choke )
Jason do you have a number I could contact you on? Thanks Michael
- The same spacer will work fine.
- Transmission vacuum modulator attached to back of Edelbrock in same way it attached to back of Rochester... via the large vacuum fitting off very back of carb. It has a large male nipple that feeds brake booster and female connector that trans line screws to. Simply transfer from Rochester to Edelbrock. See picture of fitting below attached to back of my carb and then a pic of it removed.
- I think I just used copper spray gasket adhesive to hold block plates. Once torqued down it's not going anywhere.
Can the 1406 be used without porting the intake manifold?
That is the Edelbrock carb I have on my 64 - 429 since 2006
I was running lean after installing the 1406 and the Edelbrock techs told me what to do to get the engine to the proper mixture with the adjustments they advised ( primaries needed two upgrades richer and I changed my secondaries to very slightly larger
All jets and metering rods have numbers on them so give that info to them and they tell you the next change you need to make
The local auto parts store carried the new jets and metering rods I needed then so found the parts easily
When the plugs are burning the plugs a brown paper bag color you got it right but should be done only after a very complete tune up to bring the engine up to spec in all other ways
Change ignition wires if not done in some time ( they short out to metal when the coating wears )
Due to the new electric chock you need to remove the intake manifold and plug the old choke tube that runs thru the intake — on both ends
I like the carb a lot as it installs in place of the Carter easily and uses all the stock intake spacer etc under it
When I last checked I was getting about 15 miles a gallon some time ago
One thing I really like about the carb is it has a vacuum port on it that changes the engines timing curve for improved engine performance ( they are the performance people ! )
Enjoy and Stay Safe
Thanks for the info. I looked up the specs on the primary bore diameters and found the 1406 is 1.44" which is very close to what I measured on my Rochester 4GC. The 1411 primary is 1.69" I can't get at the intake manifold to measure but assume it matches the Rochester bore.
Are there any other modifications to the intake manifold pictured above? Are those screws blocking the heat chamber in front of the primaries? Also, is my mind playing tricks on me or did I see photos here of a manifold that had been milled between the primaries to equalize pressure for an aftermarket carburetor setup?
I started off byblocking the front channel, and ends of the internal choke tube by tapping threads and screwing bolts into them and cutting off and removing the heat riser. It still was getting 305+ degree at center of intake from bypass exhaust gas across the center channel so I later blocked at the cylinder head to intake center port. If you block at the center port there is no need to block the other 4 holes in the intake.
With this thread I tried to show what I ended up with which was
1) blocking exhaust at cylinder head to intake. No need to modify they Intake other than either beveling out or fully porting to accomodate the 1411. (not needed with the 1406)
2) using a carb spacer that Russ Austin provides instead of the flimsy thing I started with
3) porting the front primaries to better match the diameter of the 1411 all the way thru instead of just beveling out the primaries with a grinding tool so the butterflies would have clearance.
Up at the very top there is a link to more of the full history of my multi-phase stab at this. Click Here for a direct link.
The stock air cleaner will no longer fit the new Edelbrock as that carbs Venturi is larger than the Stock Carter carb is
Russ sells an adapter for the Edelbrock so you can then use the stock air cleaner with that adapter
I chose to use an after market air cleaner that breathes better and can be cleaned and replaced when needed
I see Jason has the black adapter in the picture above to use his stock air cleaner to fit his own needs for the appearance he chooses
Not using an adapter myself I do see —-for the first time that this adapter does restrict the air going into the carb a considerable amount for me not to care for going that route myself
The adapter is altering the air flow into the carb enough for me to not make it a desirable addition for my own liking
The answer might be to use two air cleaners - one for the shows and one for all other times ( ? )
Just my own 2 cents as you may have your own desires on the subject