Vacuum Amplifier Question

rcmaniac791

Well-Known Member
Joined
Nov 4, 2015
Messages
225
Reaction score
68
So the canister thing on the back right of the engine, I believe it's called the vacuum amplifier. Since I'm not using the lean-burn computer anymore, it it really necessary to keep it in there, or can I take it out? I just don't really know what purpose it serves, and I have to take it out anyway to get access to the oil pressure sensor that I need to replace. I'd like to clean up some of the junk from under there. I'll try to get up pictures tomorrow so y'all will know what I'm talking about.
 

Aspen500

Well-Known Member
Joined
Feb 14, 2015
Messages
7,030
Reaction score
2,758
Location
Rib Mountain, WI
If you don't run an EGR valve, it has no purpose. It takes the weak ported vacuum signal from the carb and opens to send full manifold vacuum to the EGR valve.
 

rcmaniac791

Well-Known Member
Joined
Nov 4, 2015
Messages
225
Reaction score
68
Ok cool. I still have my EGR, so I probably won't get rid of it then. If I do delete the EGR, would I have to compensate with more fuel, or can I simply take the valve out, put a block off plate, and that's it?
 

BudW

Moderator
Staff member
Joined
Mar 4, 2012
Messages
5,121
Reaction score
1,485
Location
Oklahoma City
The vacuum amplifier looks something like this, and bolts to rear of passenger side valve cover.
Vacuum Amplifer.jpg

Basically all it does is increase the amount of vacuum coming from the EGR port on carburetor.

If you disable the EGR system, remove the two vacuum hoses marked by red X’s and plug the ports (plug the port on vacuum tree and other on rear of carburetor.
77 318-2 EGR hose routing.JPG

Note: this photo is from my ’77 FSM (Factory Service Manual). I don’t recall seeing a 49-statee ’77 318 with the EGR Dump Valve on it. My ’77 318 does not have it, either – so if your car has one, it can be unplugged, otherwise ignore what isn’t there.

The EGR timer (on firewall), Vacuum Amp and solenoid (one nut on valve cover), 2 (or 3) CCEGR valves (temp vacuum switches on intake and on radiator (most cars don’t have them on radiator)) and EGR valve can now be removed.
If you remove the CCEGR valves, then you will need to get pipe plugs to plug those holes. The EGR valve will need a metal plate (and gasket) to plug those holes.

Presto, a lot cleaner engine compartment.

IMO, if you live in an area that you can toss emissions equipment (like Oklahoma), I would recommend leaving those parts in place, if system is working. If system is not working or is missing parts, then go for it. Most people will not notice any difference with system working or removed.

If you have Lean Burn, then the computer controls the EGR operation. If your car came with Lean Burn, but it has gone AWOL, then the EGR valve (and related parts) are taking up space.

BudW
in Oklahoma
 

Aspen500

Well-Known Member
Joined
Feb 14, 2015
Messages
7,030
Reaction score
2,758
Location
Rib Mountain, WI
Without a functioning EGR system, about the only thing you MAY have is light throttle/light load spark knock. Without the EGR, the combustion is "hotter". If it's designed for EGR, the carb and ignition timing curve is calibrated for it. If you do get light spark knock, the easiest fix is to just use the next grade of fuel higher.
This is all depending on if your EGR is working in the 1st place.

Emissions 101: EGR cools the combustion process to reduce NOx and that's the only reason cars had them in the past (newer gasoline cars/trucks don't have EGR valves anymore for the most part). The higher the temperature, the higher the NOx.
 

Leizurtime

Well-Known Member
Joined
May 28, 2016
Messages
180
Reaction score
17
Location
Westminster, CA
My vacuum amplifier says part # 4041737, and it has an additional port running to a small vacuum reservoir can. I don't see many of these. I was looking at replacing mine, as I've needed to replace every emission component thus far. Do any other part #'s cross over? I was looking at one on craigslit a guy pulled off a 77 360. Part # 4041730, it too has the reservoir like mine. I wonder if this would work.
 

Aspen500

Well-Known Member
Joined
Feb 14, 2015
Messages
7,030
Reaction score
2,758
Location
Rib Mountain, WI
The '81 D150 I had 20 years ago had the port and vacuum reservoir also. It's just to ensure there's always a supply of vacuum when needed. Sort of a vacuum "shock absorber". I seem to remember from WAY back that they all had the extra port on the amplifier and if unused, it was plugged by the vacuum harness connector.
 

Leizurtime

Well-Known Member
Joined
May 28, 2016
Messages
180
Reaction score
17
Location
Westminster, CA
I was curious if the reservoir was significant. It must not be because I've seen a ton of cars without it. I actually pulled the vacuum amp off a car very similar to mine. 77 Dodge Diplomat, with 318 and AC. Its vacuum amp didn't have any provision for the reservoir, not to mention, no reservoir. The only difference between mine and that car, is that it was a lean burn car. Mine is pre lean burn....thank goodness. Also, its vacuum solenoid valve has 3 nipples instead of 2 like mine, the type I've seen with the reservoir. It has an extra vacuum line running to the manifold vacuum source. They must have opted to ad an additional vacuum source to activate the egr, instead of relying on a greater volume for the vacuum amplifier, thus they must have ditched the reservoir in that configuration.
 

AJ/FormS

Well-Known Member
Joined
Apr 26, 2016
Messages
1,291
Reaction score
305
Location
On the Circle of the earth, Southern Man,Canada
AGCO Automotive Repair Service - Baton Rouge, LA - Detailed Auto Topics - How Does an EGR Valve Work

Read the opening paragraph.
On a gasoline engine, when the temperature of the combustion chamber approaches 2500 degrees Fahrenheit, nitrous oxide emissions increase. The fuel air mixture can also spontaneously combust, causing valve clatter and damaging the engine. Allowing a small amount of exhaust gas back into the intake reduces combustion chamber temperature. Regulating the flow of exhaust gas is the job of the EGR system.

What they don't tell you is how this is accomplished or why.
As to the why, they claim Nox is damaging to the atmosphere in that it does not decay back to it's original components there, but attaches to the ozone layer, destroying it. Or some such, IMO, UN-proveable thing. So Nox is bad.
So why is the Nox there in the first place? Let me tell you; cuz the little tiny engines they give us have to work so hard to get our tanks moving. And the little tiny engines are foisted upon us cuz they took away the ability of the bigger engines to get decent gas mileage, by driving the compression ratios into the basement. And they did that cuz they are giving us skunk-pee to burn. And so we burn twice the amount of skunk-pee, to go the same distance, and some oil barons are collecting huge amounts of money from us poor Average-Joe schmucks. And since the Governments collect taxes on all this extra gas that is being sold, They too are receiving a windfall.What? Who are the they, herein referred to? Scientists,engineers, and governments.I might say that all these thets lie to us all the time, but that is a whack-O thing to say.
When we were at 10 cubic inches per pound of chassis weight, back in the 70s, those engines were lazy. They made so much torque, they could accelerate easily at part throttle, to any speed with any gear. So Nox was never even heard of.And those big engines did pretty good on gas.
Today they don't even put big engines in trucks anymore. What do we get? 287 cubers in 5500 pound tanks, and 238s in 5000 pounders; 17 to 21 pounds per cid! These engines work hard. And when the do, look-out here comes the Nox. We can't have that!
And these engines make little to no better fuel economy than the engines of yesteryear. And they are so heavily laden with computer controls that when that little CEL comes on, we panic and run for cover!
What a scam to sell ever more watered-down gas at ever-increasing prices.
And there is almost nothing we can do about it.
Ok so end of that rant.
So how does adding hot exhaust gas to the intake charge decrease the combustion temperature.
Well this exhaust is about 600 to 1000* F. And inside the chamber, the temperature may be 2500*F. So,even tho the exhaust temp seems hot to us mere humans, to the chamber temp, it is only about 1/3 the temp in there. So while it's in there it acts like a heat sponge, soaking up some heat. Heat that could have been used to propel the vehicle. So you see where this is going right? Heat is the only thing driving your vehicle forward. The heat expands the gasses, that push down on the piston, that makes the power that moves the car. And they,(the liars in power), in their infinite wisdom take some away.So we have to burn more gas per mile to heat the atmosphere.Hyup, what a scam.
In effect they are charging us and taxing us to create global warming, which they then charge us and tax us to try and reduce.Hyup, what a scam.

So, If your car is an EGR equipped car, and if you can legally do it; get rid of it. Oh wait,sorry, that won't by itself improve the situation. No, it's like a spider's web; with everything connecting to everything else.
It all starts with compression. The more you have, the more heat you can make in the chamber. And the more the heat in the chamber, the more torque the engine will make.And the more torque that you can deliver to the rear tires, the harder and faster the car will go.
And it works at every throttle setting;not just at WOT.It all starts with running as much compression as the gas will support.
In fact, if you put a little tiny carb on your engine to limit the loading on it, you could theoretically run way more compression than what would be considered normal.Cuz the engine would never be working very hard. And you could tune that little bugger to get 30 mpgUS, or more, with no computer controls nor EFI nor EGR nor any of the low-compression bandaids. And those powerful little buggers would not need big TCs nor race gears.
No they might not win any races, but they don't have to; they are commuter engines. The speed limit is 65, and they can get there on a 100 cfm carb if they had to.And because they would be back to 10 pounds per cid, they would still be pretty peppy.
You might be tempted to call me a whack-O,
But I have used this method to extract 32mpgUS from my 367 in a 3670 pound car and using a 223* cam, and a 2.0 final drive.
And this car still went 106mph @12.9 in the qtr.
So, am I a whack-O? I tell you what, build yourself an 11.3 Scr, 367, and see for yourself. Stop letting the powers-that-be dictate truth. They do not have your best interests in mind. They only want you to be a slave to the system, that they have engineered, to work us into an early grave.
Spending at least one day's after-tax wages on gas every week, and the rest on food and lodging is all part of it.Making your wife work, to support your joint lifestyle ensures complete slavery.We are so busy working to eat, and support all the blood-sucking-vampires above us,that having babies is fast becoming impossible. We are a dying civilization. This continent will soon be barren.
Well except for the muslim take-over.We seem to be making it easy for them.lol. Wait what? I was ranting? really? OK, well sorry about that,lol.
Anyway that's EGR 104.
 
Last edited:

89.Fifth

Well-Known Member
Joined
Sep 5, 2015
Messages
444
Reaction score
110
Location
New York, NY
Only one like in 11 days? Common I poured my heart out. Like MEEEEEeeeee.
Well, at least, I got no "buzz-off, whacko" s
Thanks 7T8

Huh? I read your post and it was really informative but I'm not sure anyone has anything further they can contribute. Is that what you mean?
 

Leizurtime

Well-Known Member
Joined
May 28, 2016
Messages
180
Reaction score
17
Location
Westminster, CA
Whereas, I respect your opinion, the post doesn't really address any of my technical inquiries. Its true, my car is a gutless wonder. The power is there when I need it, but I have to put my foot in her to get it. I know the smog system is whats holding it back. Nonetheless, I am required to maintain these systems in order to register my car. I'm not exactly complaining, I am an advocate of being aware of the environmental impact of our carbon footprints. I sit on 4 lane highways day after day completely packed with millions of cars and that's just in my area.

What about the rest of the world? Not to mention China, who pretty much ignores environmental concerns completely. I'm only talking about cars too, don't leave out the various power plants and industrial facilities all over the world producing emissions at a constant. You can't tell me, we don't make an impact. To ignore the possible implications simply because we want a few more horsepower today I think is irresponsible. Whether its true or not, we have an obligation to protect the health of future generations, it would be prudent to error on the side of caution, that's why I don't believe the subject should be taken so cavalierly.

Not to say, if I owned a pre-75 car I wouldn't milk every last pony I could get out of her, but I won't cry for having to smog my 77. It's the law and there are good intentions behind that law. In fact, I plan to build up my car and I have been researching California compliance on doing engine changes. I have learned a great deal, even talked to a BAR referee tech on the phone to get more details. One of the key rules is you have to swap over any emissions equipment standard for the donor car to your car and I'll have no problem doing that as long as I'm mechanically capable of doing so.
 

kkritsilas

Well-Known Member
Joined
Jun 21, 2012
Messages
1,961
Reaction score
419
Location
Calgary, Alberta, Canada
The road to hell is paved with good intentions......

The "smog" equipment doesn't really do as much as most lay people think it does. It will help if it is in good shape. It won't if it isn't working properly. For our cars, in many cases it isn't working properly, just simply due to age. And replacement parts are simply NOT AVAILABLE. Try to find a new ESC/Lean Burn computer. However, note that each car has its own ESC/Lean Burn computer, based on what engine it has, the environmental requirements (Federal, California, High Altitude, Canada), transmission type, and options. In most cases it isn't "tryting to milk out the last horsepower", but just trying to keep the cars running. Same thing with vacuum amplifiers, and a few other pieces of emissions equipment.

As for it "being the law", depending on where you are, it may or may not be. In many places, the law excludes cars over a certain age, as it does in my area. In many places a visual check is all that is required. In other places, a full hookup to an emissions tester is required. So, your quoting of "It's the law....." simply only applies to your own situation; it simply is not the same situation for everybody here. So I can modify my car any which way I want, and it is still within the law. Also, unless your state requires the emissions tester hookup, I sincerely doubt that the people who are doing the visual inspection would have the very slightest idea of what the proper emissions hookup looked like for our cars, even if they had the manuals in hand.

What I needed to get my car registered was a bill of sale, the registration from the previous owner signed off in the back , and proof of insurance . That is it; no emissions testing, no emissions inspection, no safety inspection. Pay or your $85 fee (lifetime), pick up your collector plate, and have fun.
 

Leizurtime

Well-Known Member
Joined
May 28, 2016
Messages
180
Reaction score
17
Location
Westminster, CA
Your right, it is my situation. Thats all I ever said, build your car however you want. No sweat off my sack...
 

AJ/FormS

Well-Known Member
Joined
Apr 26, 2016
Messages
1,291
Reaction score
305
Location
On the Circle of the earth, Southern Man,Canada
It was, at least, an interesting rant!
Thanks RC
Look, I know I'm paddling up-stream most of the time, cuz I believe the governments of this world are filled with corruption, and no longer have the best interests of the people or the world, in mind. But I cannot do anything about that so I don't worry about it. and I still live within the laws that I am aware of. So far I have stayed out of prison. Some day they will make it impossible,I believe.
A long time ago there was a nation, on this world,that had so many laws, it was impossible to live within them all. A new ruler entered and rewrote the law-books. That is what it will take in today's world.Law-makers are writing laws at an ever-increasing rate,mostly to create lawbreakers.
So I unloaded a bit and muddied up your thread,and for that I apologize. I am also recognized to have a somewhat strange sense of humor, but I am trying to change that.
But the message is the same.People need to question everything they have been and continue to be, taught. Trust no one, especially those in charge, and science. Or rather, modern-science.
 
Back
Top