Thanks for the additional information.
In the prior "leaded fuel eras", it was normal for the tail pipes to have a light gray color in them, unlike the black, sooty look of current eras. I wondered about this. I knew the gray color was normal and if the pipe was black internally, it meant the carb was running too rich, even to the point of black exhaust smoke.
In 1977, I had purchased my new '77 Camaro 305 and it consistently had a black color on the inside of the exhaust pipes. Yet it was running well and was averaging over 17mpg average in my driving. I inquired with our service manager about that. He asked what was not in unleaded gasoline that was in leaded gasoline. I replied "lead", to which he said it was the lead in the fuel that put that gray coating on the inside of the exhaust pipes. With that realization, I didn't worry about the color of the inside of the end of the tail pipes again, on anything. Unless I could see "black smoke" coming out of the pipe.
During the engine's "warm-up" phase, a good bit of condensate is produced as the pipes are warmed by the hot exhaust gases. Whatever is inside the pipes can be wahsed out. Some engines make more than others, by observation. If the engine is idled a good bit before driving off, more condensate will usually come out.
ON THIS NOTE, all Chrysler OEM mufflers (and many OEM-spec replacements) have some small holes on the bottom of the exhaust system. One toward the rear bottom of the muffler and another one near the bottom of the very rear pipe at the low spot before the pipe turns up before the final turn-down exit, a few inches from the pipes end. These are condensate drain holes. The one in the muffler is there for obvious rust-preventative concerns. The other one at the very rear for similar, but for the rear pipe/resonator section. If you let the engine idle for a good while during warm-up, especially in colder weather, you can see the holes work.
On a realted note, the last Walker Exhaust muffler I put on the '67 Chrysler had some literature with it that stated it had some sort of "magic" absorbent material costing the bottom of the inside of the muffler. There to collect any moisture so it could be evaporated by the hot exhaust gases after the engine was warmed-up. I could tap the bottom of the muffler and it sounded "dead", compared to other mufflers I had done that to. Seems like there was also a "Lifetime Rust-out Warranty" too? Guess it has worked as it's till under there after 30 years of limited use.
One time, about 10 years ago, I started to notice (on new Toyotas at work) that they seemed to produce a LOT of condensate. The ones I was seeing had been idling (from cold, after being outside) for a good bit, when they were pulled outside, the first throttle application resutled in up to about a CUP of condensate out the rear of the exhasut pipe. Being they were new, the water was clean.
DO check the automatic choke thermostat to see that it manually closes the choke valve with everything at ambient temps (engine, especially!) of 68 degrees F (which might mean the car needs ot be in a warmed garage in this season of the year in North America). JUST fully closes by itself. If needed adjust the choke thermostat, to get this. Then, as the engine starts, make sure the choke pull-off is doing its job, too. If needed, it can be adjusted to widen the adjustment link in the pull-off's shaft, with a wide-blade flat screwdriver, carefully. If this adjustment is a slight tad "lean", no real problem, but the link can be shortened (usually NOT needed) with a pair of pliers, too.
With that "generally as lean as it will run decently well" choke calibration, plus some tinkering with the fast idle speed screw (where the last step on the cam results in no significant fast idle speed increase over hot base idle speed), the choke should be off after the first mile (or few blocks) of driving. There might be an initial "bog" or "want to die" moment, but that can be "caught" by quickly putting the transmission in "N", followed by a quick "pat" of the accel pedal, then quickly putting the car in gear and driving off. This is where the choke pull-off link adjustment is used to fine-tune the choke's initial operation.
END RESULT is that the choke comes off, or at least off of the highest fast idle step as soon as it can while still having good non-bog drivability. And, relatedly, fewer exhaust emissions and better warm-up fuel economy as the engine is running more toward it's best fuel calibration in those times.
NOW, spark plug gap design can affect these things, too, but can be done with normal-gap style plugs. Just that the NGK V-power and later "fine wire" plugs put more of the spark kernel exposed to the air/fuel mixture for a better "POW" when the mixture is ignited, being more tolerant of leaner mixtures (as the Toyota pamphlet I found, which is where I learned of
"V-gap" plugs initially, made by NGK, OEM to Toyota and later learned of them as "V-gap" NGK plugs). Although the V-gap and fine wire electrodes work well as is, you can also get close to them by filing the ground electrode back so that it only covers 1/2 of the center electrode of teh spark plug ("J-gap" as Champion called it back in the 1960s, for "racing plugs") or hold the plug firmly in one hand as you use a pair of pliers to gently turn the ground electrode so that it only covers 1/2 of the center electrode, without changing the gap dimension (I stared doing this on my lawnmower spark plugs).
Sorry for the length, but wanted to mention my orientations on my tweaking away from "factory specs" and how they worked for me. Not everybody may want to do these things, which I fully understand. OR should attempt these things, by observation. BTAIM
Of course, when the ceramic of the spark plugs is beige-to-white, but not flaky white, then the main system fuel calibration is "in the ballpark" as to working well. Absent of the prior indicators of end-of-the-exhaust pipe internal coloration, correctly reading the spark plugs' ceramic can be more important.
Enjoy!
CBODY67