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Aluminum intake manifold
https://www.slantsix.org/forum/viewtopic.php?t=26477		 Page 1 of 1
Author:  Aggressive Ted [ Mon Dec 31, 2007 7:59 pm ]
Post subject:  Aluminum intake manifold
Today we had a day of sunshine although it was bitter cold. We have had record snow fall this year for the month of December.

The Dart has been down for a few weeks due to 15 minute fix that went bad and has turned into weeks......I had to pull the manifolds to fix the problem. At some point in the 1978 peanut plugs life there was a heli-coil installed in the last stud location that holds the exhaust manifold. I could never get that last stud to seal and quit leaking water or doing a pretty good representation of "Old Faithful". In fact the steam has eroded two gasket sets, even my "Aussie" graphite gasket! :( I had pulled the stud to try the green loctite and couldn't get it started again. So I bought a tap and the hole would not tap after about 3 turns, in fact it snapped off. Two days later with some Kriol a finish nail punch and a custom ground 4 pronged socket, I was able to get it to turn the tap and out came a heli-coil.

The new heli-coil and stud are installed with plenty of JB Weld since the casting is only about 3/8" at that location. I think the Heli-coil is longer than the hole. With the exhaust manifold off I enlarged the mounting hole so it won't pull on the stud. Plenty of room for expansion and contraction. I ordered the Graphite "RemFlex" gaskets and installed them on the manifold, stove joint and exhaust pipe. I also ported out the exhaust flange to 2.25" and ported and polished each of the manifold runners. I had a just purchased a aluminum intake manifold off ebay so I installed it stock, no porting, except for adding a EGR block off plate and filling the EGR hole under the carb with a mountain of JB Weld so it made a cone. My thought was to see if the aluminum would warm up quicker and help atomize better compared to the cast iron.

Everything went like clock work and finished up the install by 3:00 PM. The temp was really starting to drop fast. Fired it up and went for a spin! :D :D:D Boy it is spunky!

I must say it made a very nice improvement :!: It heats up much quicker! And lots of low end grunt from the better atomization. The tires break loose much easier than before.

Next is to get rid of the clutch fan and install a electric fan, cut a hole for the cold air intake and I am also thinking of switching over to the GM HEI mod.

Happy New Year! :D
Author:  DusterIdiot [ Mon Dec 31, 2007 8:53 pm ]
Post subject:  Not good...
Quote:
carb with a mountain of JB Weld so it made a cone.
JB weld doesn't like raw gas so well (nor lots of heat), it tends to dissolve and flake away in chunks as it gets innundated, just keep an eye on it, if it 'comes out' you'll have a chunk stuck in a valve one night at the wrong time...

FYI,

-D.Idiot
Author:  Aggressive Ted [ Mon Dec 31, 2007 9:02 pm ]
Post subject: 
What is a safe epoxy or putty? Is the POR-15 putty better in that environment right under the carb? What type would you suggest?

I have never had that problem on outboards or other marine engines.
Author:  SlantSixDan [ Mon Dec 31, 2007 10:00 pm ]
Post subject: 
Your story reminds me of my story.
Author:  LUCKY13 [ Mon Dec 31, 2007 10:12 pm ]
Post subject: 
This thread at one of the forums may help you with epoxy problems and what to use.

http://speedtalk.com/forum/viewtopic.ph ... ight=zspar



Jess
Author:  Aggressive Ted [ Tue Jan 01, 2008 3:44 pm ]
Post subject:  JB Weld
The JB Weld site had some good info.

Q: Is J-B Weld resistant to water and/or gasoline?

A: When fully cured, J-B Weld is completely resistant to water, gasoline, and about every other petroleum product or automotive chemical. For wet-surface or submerged water or gasoline repairs, see our J-B Stik or Waterweld product information.

Q: How much heat can J-B Weld withstand?

A: J-B Weld (Part # 8265-S, 8265, and 8280) can withstand a constant temperature of 500 degrees F. The maximum temperature threshold is approximately 600 degrees F for a short term (10 minutes).

Looks like I am safe for the intake manifold should not reach 500 degrees under the carb. If it did I would think the paint would burn off the intake manifold.
Author:  Doc [ Wed Jan 02, 2008 9:24 am ]
Post subject: 
Quote:
...the intake manifold should not reach 500 degrees under the carb. If it did I would think the paint would burn off the intake manifold.
The paint around the "hot spot" of the intake manifold does tend to burn-off over time and high speed driving.
Make sure the heat riser valve is working correctly and you may want to loosen the spring a little so it "kicks-off" a little sooner.
DD
Author:  Aggressive Ted [ Wed Jan 02, 2008 10:45 am ]
Post subject: 
Doc it works very well, I am surprised after all these years.
How would you go about adjusting it?
I looked at the flat coil spring and really didn't see away to adjust it.

On the paint, I have never had it burn off the manifold at the stove joint. Maybe it is staying open ok once hot and at high speeds.

Can you share more on this procedure?
Author:  Doc [ Wed Jan 02, 2008 11:26 am ]
Post subject: 
To adjust the rate of heat valve action you need to re-clock the bi-metallic spring or adjust the counter-weight "load". (add or subtract weight)
If your valve is working freely and is full open at 1800 RPMs, then I would leave it alone.
DD
Author:  illldeca [ Thu Jan 03, 2008 3:38 pm ]
Post subject: 
i have one of those aluminum manifolds sitting around but it only holds a 1 bbl carb so i switched to a cast one that holds a 2bbl
Author:  Aggressive Ted [ Thu Jan 03, 2008 7:52 pm ]
Post subject: 
After I log the mileage changes with the one barrel aluminum version I will try to find a two barrel aluminum version and track the mileage differences.

The SL6 sure is a fun and easy motor to work on. Tuning for torque and mileage has proven to be very interesting journey.
Author:  Aggressive Ted [ Thu Jan 10, 2008 10:40 am ]
Post subject: 
Just checked mileage after installing the aluminum one barrel intake, RemFlex Graphite gaskets and JB Welding in the heli-coil and stud on the last exhaust stud bolt location. Still not alot of heat in the car when it's freezing, but the mileage jumped back up to 23.8 mpg! :D

Pretty good for as cold as it is. That includes driving through the last two snow storms and hitting up to 65 on the freeway a few times. The aluminum warms up much quicker and runs hotter than the cast iron. During the freezing temps the cast iron #1 cylinder branch was running luke warm. Now the aluminum is too hot to touch! Number one spark plug is running a couple of shades lighter now, equal to the other plugs. With the cast manifold it was always a couple of shades darker cinnamon color than the rest.

I thought the car was spunky before......now it is really touchy and very responsive at all speeds. If any of you that live in a cold climate that are looking for better mileage, the aluminum one barrel truck intake is a nice upgrade. The casting on mine was very good quality. I did not port match the intake so there is a step going into the head. Some folks have found this important not to do.......so I thought I would try it. My old cast iron manifold was port matched. I also used the following EGR block off plate from the dealer # 3671447 lists for $6.25 used with standard EGR valve gasket p/n 4173 167 lists for #2.81

I really missed driving the Dart last month. I don't have a garage so I had to do the work in short intervals between snow storms. I forgot how much fun it is! :D
Author:  Eric W [ Fri Jan 11, 2008 1:31 am ]
Post subject: 
Good read Ted. Now I wish I grabbed that aluminum manifold that came with the exhaust manifold I'm using now from the wrecking yard!
Author:  Aggressive Ted [ Fri Jan 11, 2008 12:48 pm ]
Post subject: 
Eric,

If you go back to get it. Try to find a aluminum two barrel manifold.
I would like to try the Super Six set up next. I have all the parts except the manifold I have is cast iron. Knowing what I know now I would like to stay with the aluminum. So I am on the hunt for a aluminum two barrel manifold. Preferably the solid cast one, but I would try the welded one. I have seen a few of the solid cast manifolds and they are pretty nice, just like the aluminum one barrel that I am running now. :D
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