360 Questions.. pardon my ignorance.

So I have an update on this in case anybody is interested…

Long story short I got drastic but it paid off.

Basically after overthinking this truck and tinkering on and off for so long I decided to scrap everything I had read or memorized and started from scratch on my troubleshooting and setup..

First problem was the vacuum leak in the carb, I had seen the baseplate mentioned a few times but that wasn’t my issue at all. The main body of the carb had some distorted tabs for the baseplate screws to where the if you took the gasket out and just matched the faces together the left/right edges would touch but you could see daylight straight through the middle. Considering it was potential scrap anyway I simply took a flat file and leveled the tabs down to get a better face on the main body. Threw it all back together and tried spraying the carb like I did to initially find the problem.. fixed.

Next I moved onto the timing again. The motor has been replaced in the truck so I found the date code and it’s a ‘75 motor. Pulled out my shop manuals, both ‘73 and ‘75 called for TDC timing, I went a little higher and locked it in around 8-10. Lo and behold with the vacuum advance hooked up and the transfer slot set about square the idle speed landed around 700rpm.
Call that good.

Last was idle quality and off idle stumble.. I reset the idle mix screws to 2 turns out and it was decent but with an odd miss here or there so an extra half turn out and no more stumble.

I still have to road test it but it’ll crawl in gear, has no more stumble at part throttle and it will throw rooster tails in the yard so I’m calling it good. Sure, it probably is a little fat and lazy but considering it will just be for cruising into town on weekends it’s more than sufficient for my needs.