I was wondering what my temperature should be on a stock 350. Right now its getting up to around 205 and that seems high.

PS it has new a water pump, and i flushed and pressure tested the radiator.

205° F would be normal for a late model computer controlled car. If you are talking a vacuum advanced HEI distributor with a 160° F thermostat in the water neck then 205 is getting warm.

There will be nothing wrong with running that temp all the time. So long as the motor doesn’t get into detonation you can run up to 240° F before it starts to effect the oil (that is it’s upper limit). Pure water of course has a fixed boiling point, but coolant in today’s engines is rarely distilled water. We add antifreeze and run a pressurized system (the higher the pressure on the radiator cap the higher the boiling point of the coolant will be).

Ignition timing has the biggest effect on the motor’s temperature; then it’s the dynamic compression ratio, and then the thickness of the cylinder walls comes into play. Fuel air has a profound effect on the temperature but assuming the motor is running that has not changed (when the a/f ratio goes off the motor not only runs at a different temp but it often fails to run at all).

Big Dave