First of all the Venom 400 is an electronic module that fools the ECU into dumping more fuel. (It's not larger injectors).
2: The tornado is absolute crap. I wasted $75 on one 10 yrs ago when I was 16 and dumb. Didn't do jack. I checked my gas mileage, no improvement. I wanted to kill the little old lady in thier infomercial who said her 3 cyl. Geo had power after installing it.
3. Don't buy an electronic supercharger it's garbage.