That's a common problem. I've heard from a mechanic that I can get a chamber installed inside the tank surrounding the fuel pump with drilled holes which will retain petrol during speed turns, but I haven't tried it myself. My issue was that whoever originally installed the EFI fuel pump did it very poorly. It looked like the hole was cut using hammers and pliers, it was a real shitty job. I ended up with a leaking tank no matter how many items mechanics tried to fix it. I finally got it permanently fixed by the guy in plaza recently - he cut out the section and welded in a new one, which fixed the issue for me. It's still a jugaad, but if the fuel tank isn't available, that's better than the alternative.
I happen to have his number: 0333-2317293 (Nadeem)
Talk to him about the petrol retention issue, see what he says.
P.S.: If you get it done and are satisfied with it, do let me know, I'll get it done too.