Adventurer 96
I think there is a possibility that you are over reacting to your cooling problems so here are my comments.
First of all, like most Sunbeams, your complete temperature measuring system may not be accurate even though you have a “rebuilt” gage. If you want to know how accurate it is, remove the sensor, hook it up with enough heavy wire including a ground so that you can place it in a can of boiling water heated with a propane torch. With the ignition on, read the temperature. Find out what the temperature of boiling water is at your altitude and you can then figure out the error. If you have a 10 degree error on the high side, which is not unusual, and a 185 degree thermostat then your 190 – 195 degree temperature is right on.
Having the temperature go to 220 degrees when it is stopped is entirely normal. The temperature rises in all cars after they stop. This is because the coolant absorbs the heat from the block and because it is static, the temperature rises. Your other car will do that but it probably doesn’t have a direct reading temperature gage like the Tiger so you don’t know it. 220 degrees is no problem. if you have a proper 13 psi radiator cap it won’t blow with your mixture until the temperature gets over 130 degrees. What ever you do to try to stop this is a waste of time and money.
You don’t say what the ambient air temperature is when you are driving. That is a very important piece of data.
Yes, you must have a shroud, you will get an improvement with a better fan, seal the horn holes, seal the radiator above and below between the bottom tank and the suspension cross member. Add an air dam below the cross member. This will cause a vacuum below the car that will help suck the hot air out of the engine compartment. You can trim the radiator support that runs in front of the radiator for a modest gain but I don’t recommend it because it is structurally important. There is nothing else you can do to the front end to help much.
If you do find a Maverick or Pinto fan, you don’t have to trim the whole blade. You only have to notch the blades so they will clear the steering rack.