Yup. lol

I'm sure both of his parents owned and drove Chevy as well as smoke the old good stuff

What (if anything) did Brian at IMM say about your engine dilema?
You said you took it back to him to have it tuned? HE built it...
what was HIS advise to you? You also said you were done with shops...
I am assuming he was of no help to you?
And BTW his reputation isn't all it's cracked up to be, I have dealt
with him in the past myself as a customer, and it didn't end well.

That dude is weird. He has a face I just can't trust. And the engine was rebuilt by HIM.

That was a really annoying and waste of 2 minutes 4 seconds.

For the record, I wasn't expecting/blaming IMM for building me a broken motor. If it is broken, I probably would have assumed it was my fault anyway. IIRC, IMM set initial timing to about 34 degrees. Unfortunately, Brian forgot to give me cam specs and they seem to be lost. I just know it's something like a 238/242.

Since November, I have been driving the car every weekend. Generally I let the car warm-up for 5-10 minutes and then I go for about a 15-20 minute ride. Generally, when I've been driving, the engine runs between 180-200F for the water temp. So, it has been getting to operating temperature every time I've driven it.

As for the rest, thank you for the advice. I think I'm going to start simple and pull the spark plugs and inspect them whenever I get free time. While I'm at it, I'll change the oil (as it needs it anyway).

When the car was first built, the person who put it together set the fuel pressure to about 8 psi. At my first autocross, I ended up flooding the carb on the first turn 3/4 runs. After that incident I turned the fuel pressure down to 6.5 psi as the youtube video on tuning Holley carbs I watched said 7 psi MAX. I think I may bump it down a little more (5 psi-ish) as, like you're all saying, it seems like its running a little too rich.

I think I'll take it on longer runs on the weekend to the gf's house which is 30 miles one way and generally a 30-40 minute drive.

Adjusting fuel pressure is not the way to lean out a tune. Too much pressure can push fuel past the floats and through the jets. Once you are below that threshold [7psi], you need to be adjusting idle mixture screws and jetting.

Coolio. I'll watch some youtube videos from Holley to adjust idle mixture screws and jets.

first thing i would do is pull the plugs and see if they are black.

and also set your float level, mid way up the glass if it has that in the bowls, if it's just a screw, the fuel should be right at the bottom if you pull the screw out, engine idling when you check this...

proper idle mix tune won't have the car idling well until it warms up some. tune the idle mix after the motor is completely warm.
go around the carb (all four idle screws) screwing them in 1/8th turn (leaner) until the idle stops getting higher and smoother, then maybe richen it up just a touch from there, like 1/16th of a turn on all screws...
you can also tune the idle mix for highest vacuum reading instead of RPM.

if your plugs are real black.
for the jetting, lean it out in small steps. drive down the hwy steady cruise, maybe 2000rpm, once you are too lean you will feel some very subtle surging. from there jet it back up two sizes maybe.
because of the power valve in the primary side, the seconday jets will be larger by something like 8 sizes or so. (look up the baseline tune for your carb).

And check to see if the power valve is blown.

I'd rejet sooner rather than later. Fuel washdown of the cylinder walls can destroy your ring seal.
Another option would be having it dyno tuned.

The white smoke and the black soot can be as simple as it is pig rich. Rich can cause condensation in the exhaust if it is not driven a lot and burned out. The black soot is just the water washing the carbon out of the pipes.