set up is a 04 Silverado FBO cam 5.3 with a tvs magnuson that came with the 42lb injectors currently already at 90% duty cycle. fuel pump is a walbro 450 so I have enough there.

What I need is a bigger injector to get me to anywhere from 7-800HP probably not right away but id like the room to grow on it once I have the supporting mods like 8 rib, heads ect ect.

I saw FIC has these - 72 lb Delphi drop in for GM trucks 1999-2007
I'm currently on 91 octane but as soon as I get bigger injectors ill be running E85 will the 72 lb Delphi drop in for GM trucks 1999-2007 be enough on e85 I like they're a direct drop in for our truck style and all but how much power would they support, any info please

 

FYI injector size is roughly the rwhp on gas

a 800 goal you should be with 80s

if you want e85 size injector much larger, example 900 rwhp goal size for 1300 injectors

 

Did you convert to a return fuel system? What TVS? 1900/2300

 

Returnless - Fuel system haven't touched it much but like stated I need an injector for say 750rwhp on e85 to know I have it then ill start getting things to make the goal attainable, plan on punishing the 5.3 with tvs2300

 

750 on E85 is going to require a serious fuel system. You will need to swap to a return system with 2 Walbro 450 pumps (1 pump won't support 750) and 1000 cc injectors at a minimum.

 

https://secure.fuelinjectorconnectio...48mm-tall.html

Is what I'm thinking now

 

You need a return fuel system.