Dex

How much HP do these hold up to? think they will do 700rwhp ok? Guess i'll have to try but just seeing if anyone knows

marcuskeeler

I know that the stock injectors are good at least up to 500 Crank HP, the fuel pump has to be upgraded though to support that.

The other way is to leave the stock fuel pump in and go to 60lb injectors. The pump is running hard (good to 500hp) but at least the injectors are installed ready for more power later.

Dex

Im going to go with the GT40 pumps but was wondering if i had to upgrade to bigger injectors

marcuskeeler

Hmmm, well, after 500hp I couldn't say for sure but my tuner said the stocks were "well capable" of handling fuel demand for 500.
How much are you going for?

forensicsteve

Had to change from 39 to 60 at about 480 rwhp

Dex

700-750rwhp

marcuskeeler

Well, to get 750RWHP out of the 4.6l 3v you'll be looking much further than fuel systems LOL
Good luck though, we'd all like to see it.

Dex

oh i know

almost there!

guao

roush uses 39#

05GT550

You are going to want to upgrade to 60lbs. I am running GT500 dual fuel pumps that apparently hold up to 700RWHP without problems, after that GT40 dual pumps would be your next bet.