I think 42's alone are good to over 500HP....so with the FMU I would say 575-600+.... but you'll need plenty of supporting parts in the fuel system to go to that level... the stock rails are maxed with 42's and you will need a serious pump as well.
with stock lines and rails I have seen 485-500rwhp Safe,
but maxed.A fuel system will help,but still maxing the injector
at that level.The fmu will help for sure to get away with more
I would go with bigger injectors?I seen 530-550 with fmu!
Good luck man.
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