The marine 8.1 injectors are the 43 pounders from what I understand. These are the ones used on most supercharger applications, so these are capable of LOTS of horsepower. They come with the radix and these are the ones a lot of guys with the whipples and prochargers upgrade to.

http://www.racetronix.com/Injector_17113739.html

The homepage lists them as 42 pounders and the page above lists them as 44 pounders??? They have them also at Arizona Speed & Marine.