Well sounds like you are to the point of adjustments after FIXING THE ISSUE! Great job and good luck, you have a nice ride there.

 

The only other suggestion is to change the oil at 100 miles to verify no water in there. Plus check for any foreign material just for good measure.

 

1850-12 too new for my book. It goes up to 1850-10. I assume the internals are the same though. I don't remember now if your engine has been changed. I am assuming it is still a 360 since you have a 4X4. And since you are in Indiana I am assuming your altitude is pretty much at sea level. That being the case:
1850-10:
#64 jets. Might be a tad bit lean but the accelerator pump nozzles will make up for it.
#9 secondary metering late. Which is the same as #64 jets. Which would be better for some kind of gas mileage :-missing but a bit lean IMHO for a FE. I'd change it to Holley part number 34R9716-22. This plate is stamped "22" and equal to #65 jets.
#6.5 power valve. Here again this would help with gas mileage. But I'd change it to a 8.5 for a stock FE with a 18-20 range intake vacuum signal. Holley part number 125-85. This will kick in the power valve sooner.
#.31 accelerator pump nozzles. Good blend with the #64 jets. If the spark plugs read lean with this set up then jump to #66 jets Holley part number 122-66 and .28 nozzles part number 121-28. This 121-28 comes with two nozzle assemblies and gaskets. Of which you only need one. But that's how they service them.

Now to dial in the secondaries to your particular engine, you want the secondaries to open as fast as the engine can take. Without bogging. I suggest buying the following.
Holley part number 20-13 color coded secondary spring kit. It will include a chart that tells you weakest to strongest spring. So you can swap out the spring, knowing which direction to try, and go for a test beat. Your 1850 prolly has a "plain" colored spring. I think you'll land on the purple one.
Holley part number 20-59 Quick change diaphragm housing lid kit. This kit will make it stupid easy and quick to swap out the springs you're trying. With this you'll be able to try all the springs on the same test beat. Just shut the engine off before swapping springs.

 

It has a 390 engine. Original heads and a 1969 GT390 Mustang intake 4bl. Does that change anything? Also I drove the truck today about 70 miles and going to check the oil and plugs tomorrow. I think I have an issue with the right bank. I'll explain on next post.

Thanks!

 

I drove the truck about 70 miles today. I'll pull plugs and check oil tomorrow. Here's what I know tonight... Going apx 55 mph and letting off the gas and then acceleration it blows out smoke pretty bad. Bad enough that cars behind me back off... It does -not- smoke when just driving at steady speed. Doing some research online.

Thoughts?

 

Krewat had a post in 2006 so I thought that was too old to ask on that thread but here is Krewat's post

"Next time you suspect an intake gasket leak, try this:

1) Lock tranny in 1st
2) Rev it out to 4000RPM or so.
3) Let off the gas QUICKLy
4) Let it rev down to 1500RPM
5) Hit the gas

If you get a big blue PUFF and then it clears up a lot, that's almost 99% sure that it's the intake gasket. The intake ports in the heads were clear, I think it was the gas washing away the oil."

That is spot on for my issue but I'm not sure it is blue smoke. It is a big PUFF of smoke and maybe a little white and blue. I'll have someone look at the color better later. I will also look at plugs and oil later today.

 

 

Good news, there was no coolant in the oil. That is after 90 to 100 miles. Bad news, I lost about a QT of oil during that time. The back of the intake manifold is leaking (I think) so maybe I needed more RTV. For sure oil is dripping pretty good from somewhere. Maybe I lost some oil and burned the other oil. I'm going to have my son take a pic of the smoke. I pulled 5 plugs, 4 on the right bank and all plugs look just like the one I posted.

Compression test?

 

Compression test is a great idea. If the heads were milled that could cause an issue with the seal between intake and head. That would also explain the oil consumption and leaking. Did you by any chance dry fit the intake to see if there were ant fitment issues? You may have to pull the intake and check it for flatness and verify the ports line up correctly with your heads.

 

It smokes even more in reverse

 

Those pics are me in reverse. So reverse even has more smoke. I'm putting my plan together and might take it apart tomorrow. It has dual exhaust so I know the left side is clean without smoke.

 

That's a good tip... I'll dry fit the intake this round. I'm not sure if the heads were milled. But I'm hoping I can leave the left side on as it seems to be good. Will see what I find. Thanks!

 

Well it is blue smoke for sure. The only other possbility is that the oil isn't draining back on the left side head? Try taking the valve covers off and run the truck.

 

I will do that in the next day or two. What am I looking for with the oil? Just making sure it is flowing?

Thanks!

 

If you get it on the road, and take off and accelerate, does the smoke clear up? You quoted my post where I say to rev it up, let it drop down (high vacuum) and hit the gas again, and it puffs, but does it clear up ever?