Originally Posted by Ray ray64
Well I've got a l6 250 cubic inch motor with a standard intake manifold with a 2 barrel weber38- 38 carb but im having trouble getting the fueling right... At half throttle it looses power....
Unless you have an air/fuel ratio meter you'll need to depend on the plugs and performance to tell if it's rich or lean.
On these carbs start w/the idle and get it right. If the idle mixture screws are too far out the idle jet is too small, if the screws are barely out the idle jet is too large. Once the idle is sorted out you can go on to the main jets using the plug coloring as your guide.
But before blaming the carb, be sure the ignition timing and timing curve is correct. You should be using a vacuum advance, too.