A 4.3 putting out 200hp is going to have less Torque than a 5.0 putting out 200hp. In 2002(when my boat and engine were new) a FI 5.0 was rated at 260hp, the carbed(2bbl 500cfm) 5.7 was rated at 260hp. On the water my 5.7 blows away the 5 liters by a long shot.
As I said I did use a Holley 650 spreadbore and that it did preserve a lot of my torque with the bigger prop. With the smaller prop, the holeshot was better with the 650. At WOT the secondaries were not fully opened as a 5.7 @ 5000 rpm doesn't not require more than about 435 CFM. Before you say I had a 500 CFM 2bbl Holley on it, note that 2bbl and 4 bbl carbs are flow rated at different pressure drops. The 500 cfm 2bbl is really 1/2 of the Holley 3310 4bbl, which was rated at either 750 or 780 cfm(depending on what year of catalog) so the 2bbl, when flowed like a 4bbl, is about 380 cfm, a little too small for a 5.7. But it is just about perfect for a 5 liter turning 5000 rpm.
A 4.3@5000 rpm with 80% volumetric efficiency will use about 300 cfm.
Holley does make a small squarebore 390 cfm marine carb. I don't know too much about the Edelbrock carbs other than they used to be Carter carbs, and my experience with them was on Chrysler cars and trucks. You always carried a screwdriver to stick in the choke so it would start. The smallest Edelbrock carb is 500cfm