I rebuilt my 302 and I cannot find a new intake manifold that works with my vehicle. I got an Edelbrock 3723, because Summit said it would work with my vehicle. I went to put it on today and realize there is no opening for my choke heater. Called Edelbrock and they said they got nothing for me. Does anyone have any suggestions? Is there a way I can rig this to work? What would going to an electric choke involve?

Edelbrock has a 1403 electric 4 barrel, but it is not 50 state emissions. My vehicle has is EGR also.

 

Electric choke is easy. Assuming you have an ammeter instead of an charging light, you run the wire from the choke down to the S terminal on the back of the alternator, which isn't currently being used. That will provide ~6 volts to the choke's heater, but only when the engine is running. Then you adjust the choke until you get the engine to start properly when cold - just like w/the heat stove.

 

I don't quite understand why an aftermarket intake manifold won't work with your vehicle? On my own 1985 302, the stock hot air choke went from the choke cap to a choke stove chamber on the side of the passenger's side exhaust manifold. The electric assist portion of the choke ran a single wire from the choke cap to the back of the alternator. The intake manifold had nothing to do with the hot air choke on these trucks.

Clean, filtered air from the air cleaner is pulled through the "fresh air" tube (a rubber hose that is connected to the carburetor air horn and attaches to another metal tube) and into the bottom of the choke stove chamber on the passenger's side exhaust manifold, where the air is heated up when the engine is running. From there, the heated air goes back up through the insulated "hot air" tube (attached on the top of the choke stove on the exhaust manifold) that attaches to the choke cap. As the air gets hot, it closes the spring in the choke cap, which allows the choke plate to open up as the engine warms up to run on a leaner mixture.

The "electric assist" portion of the stock choke does not work on its own. In fact, it doesn't have to work at all in order for the hot air choke to be effective. It is only there to "assist" the hot air choke in temperatures above 60 degrees, where it helps the choke come off sooner for cleaner emissions. It doesn't work at all when the weather is colder than 60 degrees.

An aftermarket electric choke is easy. The original hot air choke is better because the full opening of the choke plate on the carburetor corresponds with the time it takes for an engine to reach normal operating temperature. The heat from the exhaust manifold opens and closes the choke in relation to how hot your motor is. By contrast, the aftermarket electric chokes go from closed to fully open in less than a minute, which causes hesitations, surging, and stalling unless the weather is warm outside. Another drawback is that an aftermarket electric choke resets every time the engine is cut off, which sometimes will choke your engine when it doesn't need it at all, for example when you stop to get gas and start the engine again.

 

I agree with Lariat 100%, especially the part about them sometimes choking the engine when they don't need to.

 

While I agree that an electric choke isn't the best, they do work. If hooked to 12v they certainly will heat up too quickly, but connected as shown in the factory shop manual to the S terminal they take a lot longer to beat up, and that extra time makes all the diff. In fact, the one on my truck does pretty well. No, I can't run quite as much choke as I'd like or it'll come back on too quickly, but where I have it works fine if you let the engine run for 30 seconds before dropping it in gear when it is cold out. I get along with it fine, but wouldn't ask my wife to drive it in cold weather unless I started it for her.

 

I have found that when the carburetor is set correctly, and the hot air choke is set correctly and functioning, a carbureted vehicle will start just as fast as any modern fuel injected vehicle. The weather got down to 10 degrees last winter in South Carolina, and my 1985 F150 actually started right up with one single pump of the gas, and remained running without stalling at all. I am also running the stock thermostatic air cleaner and it is hooked up correctly. For some reason, people like to throw these away because they "clutter up the engine" when in fact they help driveability in cold weather and also doubles as a cold air intake.

An older carbureted vehicle can run just as good as any modern fuel injected vehicle provided the carburetor is set correctly, the hot air choke is set up and functioning correctly, and the stock thermostatic air cleaner is in place and working!

 

Agree completely, which is why I'm saving the cold air ducting and sheet metal that goes around the exhaust manifold from the '85 parts truck. All of that was missing from my '82 and, with the electric choke, it needs all the help it can get. The ability to get warm air quickly and cold, or cooler, air when it is hot outside certainly helps - although the latter isn't a choke issue.

Yes, the electric choke isn't the best but it can be made to work. And the '60s era 2150 that I've been running, awa the '85 Holley from the HO that I'm going to put on at some point, only have an electric choke. In fact, so does the Edelbrock 1406 that is destined for Dad's '81 351M, but I will put it on the '82 Explorer in the interim since I'm confident it'll get better mileage than the Holley. (Yes, I'm biased.)

My point to the OP is that an electric choke can be made to work. If that's what you have to work with go for it. As L85 correctly points out, a carb'd engine can give good driveability, but one with an electric choke may never be to the "start & forget" point.

 

My choke stove drops down inside and bolts on to the intake manifold. I've had some people tell me theirs was in the exhaust, but mine is not. The only things feeding off of the exhaust are for the EGR. I think what I'm leaning toward doing is trying to find a new carb with electric choke. Either that or trying to rig up a manual choke.

 

For 1985, the 302 could be had with either a 2-barrel "feedback" carburetor or electronic fuel injection.

If your truck is still running the *original* 302 with a 2V Motorcraft carburetor, then it would have originally had a hot air choke with electric assist. It would not have a "hot water" choke unless someone replaced the intake manifold.

ALL of the aftermarket carburetors I have ever seen use a fully electric choke.

 

My 1981 which has a 351W and runs a 4180 Holley does fine with the electrical choke
on it. I do adjust the choke setting differently in hot weather here in North Carolina
than I do in the cold months.

 

I know exactly what you're talking about, my M-block's manifold has that setup.

My guess is that you don't have a 302; those engines have a coolant crossover in the intake manifolds, whereas the M-blocks have an exhaust crossover.

Intake manifolds are not interchangeable.

M-blocks (335 series) engines are:

302 Cleveland (Australia only)
351 Cleveland
351M
400

How many bolts hold each valve cover on?
.
.

 

The engine is a 302 with 2 barrel carb, and it is the original engine in the vehicle. I know it was made in Canada (maybe they all were I don't know) and it has EGR. As you can see there is not much to it. The valve opens and closes and there is a single air line that feeds back up to behind the carb. There are 6 bolts on each valve cover.

I guess I could always just run an line up to the cab and blow in it when I start the truck. People watching will just think I have a breathalyzer.

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You're right, I just looked in the parts catalog.

You're looking for an intake manifold? 1985 302?

BTW I made your pic show up inline, makes it easier to see.
.
.

 

That is the "flapper valve" that was in my 351W HO's intake manifold. We've been speculating on why it is there in addition to a heat riser valve since it would seem that either would have done the job. With no vacuum on it the thing is closed and doesn't allow exhaust to flow through the heat riser passage from one side to the other.

It really doesn't have anything to do with the choke. However, it does have an impact on how quickly the intake gets warm, which does effect how much choke the engine needs. But, if it isn't hooked up properly, or if the upstream controls aren't working properly, it will remain closed and actually slow how quickly the engine warms up.

I'm going to leave it off and block the hole with a plate that I'll make. And, I'll leave the heat riser valve in the exhaust out. With that I'll be back to where I am today and the electric choke will suffice.

 

My engine code is C1 (Cleveland PLT 1).

So, do you understand my issue now? My Edelbrock intake manifold I purchased does not have a place for me to reuse the heater choke assembly in the picture. I really have no info on it other than my repair manual says it is a choke heater assembly.

Any suggestions on eliminating it? I've talked to a few manufacturers and they all say they do not have aftermarket intakes with this option.