Fuel injection

Most comparison tests show little or no difference in peak HP between the bolt on Sniper type systems & a 4 bbl. Main benefit seems to be easier starting etc.
It still uses the intake manifold, so all the vagaries for THAT manifold will remain with EFI. In this scenario, the only thing that is really different is the injection pressure between carb & EFI.
BOTH use pressure; carb uses atmospheric, EFI uses a higher pressure generated by a pump.

If it was my engine........
Spend the money elsewhere. Get a GOOD reliable carb [ that would be any carb except a Holley or clone ] & tune it. If you cannot tune it yourself, have a professional do it. Two good trouble free carbs would be an Edel AVS or Carter TQ.