Need help, what jets should I use?

Here’s the deal I have a 383 with an EFI intake manifold and throttle body. The car is putting out 430-440 hp N/A at the wheels on a Mustang dyno. I have added a N2O Powershot plate which is for a carbureted motor with 4-5 psi fuel pressure. I tried to use the sizes called out for a TPI system (71 nos/53 fuel) but that was fat, my air/fuel ratio was around 9 to 1 with those jets. So I was wondering if anyone has done this kind of set up and if so what jets are you using?

This is the nos behind the throttle body plate?

I think I'm running 71-40, but I'd have to check when I get home. It depends on your fuel flow. The tpi 150 jetting assumes that fuel pressure will drop 3-5pounds so they fattened up the fuel side to compensate. Mine was rich off the scale when using that jet combo. You will have to order some various size jets in between what you already have and play with the fuel jet to get it where you want it. I bought mine from a guy on ebay that sells any number size jet you want in packs of 6, so I got a 36, 38, 40, etc to fill in what you don't have. I think my a/r was 10.9-11.2 with the 71-40.

Call NOS and tell them what plate, and your fuel pressure and they can get you the jetting.