New to me 78 NYB on its way but please Don't tell my wife

Intake gasket drawing air on engine side/lifter valley. Causing oil fouling, and cylinder running lean. Check torque on intake bolts, you did use thread sealant on intake bolts right?

I’ll check. Good idea! I like the simplicity of the suggestion. I’ve got a long carb cleaner straw I can use to squirt around there cold and warm to check effect as well.

As to sealer on the intake manifold bolts... I missed that episode and would not have known to do it at all.

Not to be argumentative.... but rather curious... don’t the 440 blocks have a separate valley cover between heads? Also, if I remember correctly, the intake manifold sits clear and separate from the internal engine air volume. Are you suggesting oil would travel up the bolt and past the gasket to intake runner?

I like the air leak idea which would go with the #6 being dead hot but not cold. Cold; the idle enrichment circuit could mask an air leak at idle some but it would have to be a pretty bad air leak to make it miss so badly under power.

thanks for the advice and ideas.

it’s going to be something simple like that.
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Update on the oil in the cylinder .....

checked a few cylinders (cold) and all let out an equal puff of oil with the plug out on a testcard. We appear to have more soot than oil here....
As to sealer on the intake manifold bolts
Are you suggesting oil would travel up the bolt and past the gasket to intake runner
The bolt holes go all the way through toward push rod passage/area. Can pull oil up through the threads and small surface area toward intake port.
My standard is the paint both sides of intake pan with High-tak/aviation gasket cement, + thread sealer on bolt threads.
The bolt holes go all the way through toward push rod passage/area. Can pull oil up through the threads and small surface area toward intake port.
My standard is the paint both sides of intake pan with High-tak/aviation gasket cement, + thread sealer on bolt threads.

checking now cold. What thread sealer do you use?
Going back through this thread, block came with intake from builder. Bolt is tight but had what looks like oil around it. Only bolt on intake with oil around it. Good paint under it .... so oil (or whatever it is) must have come after engine was painted, installed and started. Cleaned it out to see if it comes back.





I can see that part of the inner top of the heads is exposed to the internal air volume. So 70bigblockdodge may be on to something.
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Oil can wick up the bolts on the intake, had this happen to my 440, but pulling the intake isn't such a big deal IMO. Just 8 bolts and some linkages. Maybe you'll luck out and only need some thread sealer and a new valley pan.
If you do pull the intake make sure to high tak it around the ports, ( indian head works also). Ultra black rtv at ends toward head block intersection and across the china walls.
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Before I start tearing into the engine and checking **** hot. I started looking at the simple things first. First, checked the vacuum lines for splits or leaks. Then disconnected all vacuum lines and plugged them up... no change. Then went adding them in one by one until I was done... no change.

I noticed that the A/C compressor clutch was not engaging when warm. Checking line voltage at the switch and found it was just over 11 volt.... NFG.

Checked the power level at the battery terminals 12.2 volts. Also NFG.

I had swapped out the battery thinking that age and time in the shop had killed it. It was well into its third year after all.

New battery in at 12.6 volts.... battery terminals still feeding 12.2.... NFG. That left alternator or voltage regulator. Checked voltage regulator and it appears to be fine with power to fields steady and topped out and terminals tight.

Alternator then.

Low voltage also plays havoc with the ELB computer..... well as give you a crummy spark.

Ordered a new alternator last Saturday and got it on Thursday. Nice one. Real pretty but ,best of all, says it can put out 130 Amps under full load. Hell, I only need half that (though I do have that rear window defogger still left to wire up..)

Put the new alternator in and she runs better but the miss is still there..... just less so. Guess the hotter spark from full voltage helped.

getting closer....


New pretty alternator


Voltage output after it settled down.


Initial voltage at start up with weakened battery.


Just for fun... saw it and thought I’d share.
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And……… I’m back. I’ve been a bit busy of late

busy at work, busy on the work on my house, busy moving furniture and 30 years of parts, guns and personal crap around and between houses, busy dealing with college returned daughters, busy keeping the fleet up and running, just being very busy…… has kept me away from posting but not some progress.

In my down time, I’ve gotten closer but not solved the miss issue on my rebuilt 440.

First…..thanks to all for their advice to date.
It’s been helpful but still no winner yet on the cause. Just definite losers.

Loser number one: it ain’t the ignition….
new wires, plugs rotor and nos cap later… Miss is still there.

In an effort you can only ever call extreme. All new temporary test ignition….



Ok….. no laughing. It worked great but miss was still there….

my friend Ivan kept gigging me that it was the carb….

So yesterday….. unbeknownst to me, he took off the exquisitely running and tuned Thermoquad to put on a plate and run the smoke machine through the intake …. No leaks from the intake he could find at all. But if it’s leaking through the engine side or very narrow, the smoke may be “filtered” clean.

so the next rediculous test was… run something other than the Thermoquad…….

Stan’s gonna love this….




note to Stan….. it was exactly the same. Easy start, smooth acceleration, if a little leaner requiring more throttle to hold idle right out of the box…. but miss and rough idle still exactly the same.

we have now run out of options or obvious possibilities and will pull the intake…. I will solve this…. I will be able to stand a silver dollar on this engine again.

I am still Spartacus.

stand by
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I also have been working on an aesthetic improvement to go with the salon top I put on last year. Should be here Tuesday with a bit of luck.

can’t wait.
Spartacus is tired.

I pulled the intake and it looked to be fine.
No cracks and gasket was fully seated and tight.





the only thing “off” was that the mating surface of the intake was a bit proud on the ends by about 2 mil.




Not enough to make a difference, but it’s now flat.

result: same ****.

miss/vibration/issue still there. Most pronounced at about 1200 rpm with no load. Frequency directly related to rpm.

Very disappointing and frustrating.
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