440 Intake Project

73Coupe

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No matter how much I tuned it, it just wouldn't run right. It ran OK, got about 12mpg, had good power on the highway, but ran sluggish around town. Plugs always fouling with oil after a few 100 miles. Compression was perfect - each cyl. at 150 psi dead on. Replaced stem seals, but still oil. So, decided to tackle the intake gaskets and valley pan. Figured this was a good opportunity while the AC compressor was off getting rebuilt...

BEFORE pics:

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If you look at the pics below, you can see one intake runner appear dry and the one next to it look "wet". That's oil in there. The head side looked a lot worse. It had the consistency of sap.

The valley pan underside showed signs of exhaust leaking into the valley too.

There was insulation blankets sandwiched between the top of the pan and the intake - probably to keep oil from burning on the underside of the pan.

ALSO - found some lead deposits in the valley! These have been there for a while. Apparently when lead gets in your engine, it settles and doesn't leave. This is highly toxic **** - tetraethyllead - transdermal and will seriously F you up! The next day I had a headache even though I didn't make contact with it. I did my best to get most of it out of the valley.

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Yeah it's a wonder how anyone ever survived all those years pumping leaded gasoline for what 50 odd years? Sheesh
 
I have to ask you why the different plugs? Your EGR gasket is blown. Oil creates carbon which builds like a dirty cyrstal. The valley pan gasket is there to keep the lifter gallery clean. The insulation is there to prevent heat soak to the bottom of the runners in the intake.

Lead. Yes it is very bad and we all have too much in us. All the lead that was ever in the environment is still in the environment. The older you are, the more lead you have in you. You cannot get rid of it. I cast bullets from lead. All you can do is be aware of it and treat it like you would asbestos and fiberglass or any other thing you can think of that is bad for you.
 
I have to ask you why the different plugs? Your EGR gasket is blown. Oil creates carbon which builds like a dirty cyrstal. The valley pan gasket is there to keep the lifter gallery clean. The insulation is there to prevent heat soak to the bottom of the runners in the intake.

Lead. Yes it is very bad and we all have too much in us. All the lead that was ever in the environment is still in the environment. The older you are, the more lead you have in you. You cannot get rid of it. I cast bullets from lead. All you can do is be aware of it and treat it like you would asbestos and fiberglass or any other thing you can think of that is bad for you.

I had installed a new set of NGK plugs, but then with the constant fouling I was experiencing, had replaced a couple with the old Autolites after blasting them clean.

The EGR gasket appeared to be intact, actually. It was the intake gasket that was the culprit. I will post some info on here later on about new EGR gaskets being incorrect, along with more pics of the finished project.

As for lead and other heavy metals...I heard about modified citrus pectin for a little relief: http://www.lifeextension.com/magazi...cer-metastasis-heavy-metal-toxicities/page-01
 
Pics of the cleaning and painting...

I got a "performance" valley pan with the exhaust block off. The goal here is to keep the carb cooler, and keep intake air temps a tad lower. I opted to punch a 1/2" hole on the right side so the choke stove would still work. This might eventually burn into a bigger hole, though from corrosion.

After startup, had a few carb issues. It took a while for the choke to open, then the fast idle cam somehow was binding so it didn't kick down to hot idle. I played with bending the choke linkage, tried that out for a week, driveability went to hell on the warmup cycle. Too much stumbling while driving after a few minutes warm up in the driveway. Then the choke was sticking open so I had to manually reset it before I started the car each time (PITA). So I bent it back. Still not good. Then I disconnected the electric choke. Bingo! Works perfect now. I will also reconnect the exhaust manifold stove - need a new temp sensor in the air cleaner, and the bolts holding the sheet metal to the logs broke off, so have to extract those which will involve removing the log to work on it. I am procrastinating on that project.

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Here's the EGR gasket issue mentioned earlier. This is what NAPA, O'kragen, rock auto list for my car. It is a bust...had to make my own. Anybody run into this one yet?

Also, that vacuum line molded hose "assembly" that connects to the vacuum amplifier.. This one is getting pretty brittle, keep breaking the ends off. Do they make new ones of these?

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Here's the EGR gasket issue mentioned earliher. This is what NAPA, O'kragen, rock auto list for my car. It is a bust...had to make my own. Anybody run into this one yet?
Yep. Had to make my own. 5 minutes.

Also, that vacuum line molded hose "assembly" that connects to
the vacuum amplifier.. This one is getting pretty brittle, keep breaking the ends off. Do they make new ones of these?
Again, DIY.
How. I don't know.
Been looking for years for any info from someone who has done it properly.

I'll bet Mr C or Rexus31 knows.
 
Make a metal block off plate cut from the center of the old valley pan for the EGR. Then put a small BB in the vacuum line to the amplifier so you do not get a vacuum leak from the broken brittle pieces. Looks stock but its not.
 
On the vacuum harness, the ends get stiff, but the molded end and the hose close to it stays soft. I break off the brittle rubber and use plastic hose inserts to splice on as much new vacuum line as I need. Replace as needed from the splice point.

If done right you can't tell it's been spliced.
 
On the vacuum harness, the ends get stiff, but the molded end and the hose close to it stays soft. I break off the brittle rubber and use plastic hose inserts to splice on as much new vacuum line as I need. Replace as needed from the splice point.

If done right you can't tell it's been spliced.

That's a good idea. I wonder if anyone sells "original" style vac hoses with the painted stripe? That might be getting a little OCD, but when I got this car I had all original hoses - vacuum, heater, even fuel. My heater hoses that used to have a pentastar and part number on them now say "made in mexico" (but I turned them so that faces down). I like originality as much as possible.

Anyways, once the engine was back together, it was like a new engine. NOW I know why folks like 440's. It has a lot more power, is louder, starts and drives like a charm. No better gas mileage though, infact a little worse. I might need to reduce the main jets back down to stock.
 
I'm surprised the mpg did not go up after getting rid of the vacuum leak, are you sure the EGR valve is cycling properly.
 
I'm surprised the mpg did not go up after getting rid of the vacuum leak, are you sure the EGR valve is cycling properly.

Yeah me too. The EGR works, I can see the valve stem move when the throttle is opened. And the EGR gasket was never installed incorrectly or leaking. The EGR diaphragm holds vacuum when tested.

The engine was previously tuned with the leaky intake gasket, so (unknowingly) compensated for the leak with bigger jets. My hunch is it's running on the rich side now, although the exhaust smells good.
 
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