Changing fuel injectors 5.4 L
 

Has any one changed injectors from the stock flow to a higher flow rate? From what I gather the stock rate is 19lbs/hr. The extra horsepower I expect to make calculates out to about 26-28lbs/hr for the flow I need. Can I expect any horsepower gain/throttle crispness from just replacing the stockers before the mods start? How about tuning the engine with a tuner?

Dont change injectors unless you are supercharging and only do that once it is supercharged. Do your fuel system and injectors at the same time as an install with the s/c

In searching and reading what I was told the stockers should be fine till the power level goes up from mods (heads/cams/etc.). Found a lot of math to calculate sizes. An increase in pressure would be mre help now. I'm gonna get a reprogrammer for an axle change so I'll add a bit of fuel too. obtw no supercharging is in the future. Never have and never will.

then u will be fine with the stockers .. maybe, and i mean maybe change out to 24 lb when u do a heads/cam swap with a ported intake ...

I've started taking the inlet/exhaust restrictions out and max tuned it on 93 octane. I've done 0-60 times using stock A/F @ W.O.T. then went to 10% richer setting and no diff at all. Am I reaching the stockers limits? I'd like to change to 24's for the better spray pattern at least. obtw the mpg's went up 20% (2.0mpg) with my foot in it.

I switched to 21lb. units for the heck of it. I thought I'd try Accel and it has a crisper throttle response than before. Might just be the spray pattern? It was worth it to me for the money spent. I changed the values in the tables to match them also.:pimp:

There are no gains to be made with fuel injectors alone. Kaboom, what are your plans for the truck? Is it a pi or non pi motor?

It's a PI engine being a 2002. I've been tuning on the MAF transfer function table to bring F/As in line.:bomb:

Had much luck?

oh and what are you using for tuning? Tweecer? SCT?

SCT LiveWire with Pro Racer Package.

That live wire looks nice, does it work well? shift light looked like a joke in the pics. For the money its really hard to beat the sct stuff.

It works great. I have the alert light setup for a few PIDs. Shift light gets my attention too. I can datalog real time onto my laptop. Just select what you want to see.

I've tuned in the injectors over time since I put them in. They are now at peak performance. The tires break loose on dry pavement and all I need is 1/3 throttle. That's enuff to get into 60%+ on load and 9-10" of vacuum. Incredible throttle response also. :pimp: