I must be missing something. The OP says he already has a holley 110 pump, Holley rates that pump @ 88GPH at 9 PSI. The op’s engine makes 500HP (corrected). When doing the MATH, that pump is more than enough (IMO). Let’s run the numbers. 500HP X .5 PPH / 6 (weight of fuel) = 41.66 GPH. Now having over 112% reserve seems like enough to me. And the OP will be running, for the most part, in air that is not as good as “corrected” air, so he will need even less fuel.

I am sorry but I went down this road once. I had a car making 675hp with a holley blue pump and was told “pump is too small, you NEED a bigger one”. I didn’t have a lot of money, so I skimped, saved and sat out some races until I could get one. After all that it didn’t make the car ANY faster, so now if the numbers don’t make sense, I don’t do it.

Joe