4 barrel EGR

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Jul 23, 2007 | 01:40 AM

fordfan28

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4 barrel EGR

If I put an edelbrock EGR 4v manifold and the 4v egr spacer on a 400, what is the simplest way to control the EGR valve? I have none of the original vaccum controls / devices with the motor so I was wondering what the minimal setup that would work would be? I have a edelbrock 1406 carb.

I know I need the EGR valve itself, so what are the other devices needed to control it?? This carb doesn't have the "EGR" port so is it even possible?

I was running the carb on a non-egr intake and it definitely pings, not all the time, but enough. I broke the intake while changing the intake end seals (Don't ask - really stupid mistake) and since I have to get another one I thought I'd get the egr version and hook up the egr.

I feel like I could convert it to eec-4 faster than figuring vaccum controls out!

Jul 23, 2007 | 06:49 AM

Ranger1F150

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Don't know about your state laws but I wouldn't worry about EGR. I am not running any EGR or any emissions stuff on my 79 bronco. I am still in the process of getting a new creat motor running. In MD anything 20 years old or more you can get historic tags and never have to do emissions.

Jul 23, 2007 | 04:16 PM

fmc400

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From: Austin, TX

If you want EGR, at the very least you will need a ported vacuum switch that threads into a water jacket. It lets vacuum pass through it above a certain temperature and closes it off at anything underneath. It has two ports - one will go to the EGR valve and the other goes to ported vacuum on the carb.

However it sounds like a lot of trouble to get EGR running. If you rejet your carb and install an adjustable vacuum advance on your distributor, you can get away without running EGR. I don't run EGR on any of my vehicles because in each case, the EGR valve went out, and it was cheaper\easier to get an adjustable vacuum advance than a new EGR valve.

Last edited by fmc400; Jul 23, 2007 at 04:18 PM.

Jul 23, 2007 | 05:39 PM

fordfan28

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So the temperature vaccum switch is required - I think I understand how to hook that up - is there another controller between that and the egr valve itself or is that all you need?

Without the EGR - is the vaccum advance the only adjustment that needs made to take out the pinging, or do you need to change the weights and springs to adjust the mechanical curve as well? The vacuum change is simple enough, but I can'tfind anyone around here with a distributor machine to do the weights and springs correctly.

I've read the threads about changing the curves to match the 71 numbers and that makes sense.

I may need the EGR for emmissions visual inspection anyway, so that's why I'm considering putting it on the engine.

Jul 23, 2007 | 05:57 PM

fmc400

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The ported vacuum switch is all you really need. There were some advanced setups in the early 70's that had sensors and vacuum solenoids for ambient temperature and vehicle speed, believe it or not. However they are not common and not necessary.

Chances are you will be able to get away with just the adjustable vacuum advance, but you may need to get richer jets. It will be trial and error. You should be able to get away without changing the weights and springs, though.

Jul 23, 2007 | 10:33 PM

Torque1st

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If you need the EGR. Remove the EGR system from a similar junkyard donor vehicle... Otherwise check out some vacuum diagrams at AutoZone's website. They have the basic controls shown. Some controls are no longer available except in salvage yards. There are a number of components needed including vacuum amplifiers, check valves, and delay valves. If the EGR is not required it will be easier to just adjust the vacuum advance unit.

Jul 25, 2007 | 12:21 AM

fordfan28

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Thanks to all for your thoughts. I can't believe how many EGR valves there are to pick from. I think Napa has at least 7 different ones that could go on a 79 400. Then there are 4 ported vacuum switches - unbelivable -- EFI is so nice compared to guessing / trial and errot, etc. Maybe this will frustrate me enough to breakdown and buy a tig to weld the injector bungs in. (Joke)

I'll try to find a working system on another vehicle and copy it, but it will be tough as most people have gutted these parts years ago.