The 500 does have a propensity to bog on fast throttle opening. I used one on a 302 V8 for a while and finally got it to perform well on accels with the right combination of pump cam, pump squirter, carb heat, inlet air heat, and power valve.
If after fooling with all these variables it still bogs have the metering block surfaces fly cut. As built they are unmachined and sometimes not flat which leads to aeration in the pump squirter circuit.
Look at two I flycut. Note that after a .005 cleanup cut they still do not clean up completely. The pump squirter transfer boss is often the last area to clean up. Also notice the carb on the left and how “spongy” the metal looks. Pray you don’t have one like that.
The 350 and 500 share some components but base plates, metering blocks, booster design and venturii sizes differ. If the bowl designs are the same (cathedral or side-fill) then floats and inlet needles can be interchanged.
