tcleaderman has it just about right. Setting the timing first is the best way to go. His back set from "Max Vac" is also a good idea. Then set the mixture for max vac and you should be OK.The only issue I have had, hot starts or other wise. Is mine wants to stumble just off idle. After the max vacuum is set with the mix screw, I have to back it out(rich) about 1/5 to 3/4 turn. I think the power piston is a bit sticky with the crappy gas we have here in Utah. The local altitude is about 5000 feet so when it works it works anywhere I have gone. Hot starts can be an issue. 2 pumps on the pedal is all I have ever needed. We do have hot days(over 100F) so I cheated. Put an electric fan on with a switch. In town there is not quite enough airflow for short hops to cool down properly. 5 min with fan and it has. Then the fan is turned off and all is good. The fan is behind the grill and is run as a pusher. The last test I do is simple and kinda fun. We have a hill, about 1.5 miles long right in the neighborhood. I come up that hill at wide open. It will tell me right now if it is gonna ping. No ping? Stop at the top and add a little advance. Repeat and wait for some random pings. Turn it back just a bit and forget it. If it pings Turn it back until it stops. If I drive it daily(most of the time) no problems. Starts cold and works all day. If I let it sit(3 days or more) the check valve will bleed off and it takes a bit to start.Mine is a 235(2) all stock. in a 52 1/2 ton. So the stock fan is too low and I think that is why it won't quite cool the swamp heat on short trips. There is a Tech Tip that shows how to relocate the water pump. Using a 21 pump and a mount. That also lets the radiator set in the proper place. I can't remember, but others will who makes a "kit" with all you need. If you still have the 216 then no problems. The 235 was in the pile of rust I got as a project. So it got used.

Steve H