Most of our engines we run are 484 to 526, and I do not have the dyno experience others have, we have found the 4150 based annular carbs are always slower at the track. I think they flow a little less air. On the street they work great, but the track, the down leg ones are quicker. Especially with 50cc pumps.

Now we did dyno a 572 Hemi last year, and with a modified six pack of all things. That setup was within a dozen hp of a 4150 carb.....But on the street, it wouldn't even get out of the drive way. We learned, the dyno covers up a lot on the low end of the curve. That setup had a wicked stumble.

https://www.youtube.com/watch?v=WYw6RA-k5Bk