LN3...19lbs

will L27 injectors help power, if the chip was tuned for them?

with a NA motor

with a higher lbs wouldn't it mist the fuel better?

3400 injectors are 23-24 lbs. could those be used?

99 and up... any 3400 really

I have heard that for each lbs you raise the hp will be affected 2hp

with 24 lbs injectors thats 10hp, and the ECM won't dump fuel with a tune it will just produse more power on demand and how knows they may help gas mileage

Thanks for inviting me to the conversation...

Using bigger injectors or boosting the pressure will only be a gain if you were maxed out before. Putting more fuel in there will only make more power if it all burns. Since most systems go "open-loop" at WOT (they quit sniffing and making intelligent decisions about pulse width on the injectors), more fuel might help a lot. Or not at all.

Before I invested in a pricey set of bigger injectors, I'd probably get a regulator I could adjust and turn it up 3-5 psi. If I saw a gain in WOT performance, then I might seriously consider getting some bigger injectors and turning the pressure back down. Then sneak the pressure up a little at a time until I stopped seeing a gain. You can use the pressure to fine tune WOT performance and let the control module adjust the pulse width to give you an economical and efficient mixture at cruise.

Electronic injectors already atomize the fuel pretty well (if they are clean) but an extra 5-10psi sure won't hurt. It will make quite a difference in flow.

The following equation is used to calculate the flow if the fuel pressure is changed:
F1 = Rated flow of the injector at fuel pressure P1 in lb./hr
F2 = New flow of the injectors at new fuel pressure P2 in lb./hr
P1 = Rated fuel pressure in PSI (usually 43.5 PSI)
P2 = New fuel pressure in PSI

F2 = (F1 * P2) / (P1)

Example:
Rated flow = 19 lb/hr
Rated fuel pressure = 43.5 PSI
New fuel pressure = 55 PSI
New Flow (F2) = (19 lb./hr * 55 PSI) / (43.5 PSI) = 24.02 lb./hr

Raising the fuel pressure of a 19 lb/hr injector to 55 PSI raises the flow to 24 lb./hr.

Please note that some injectors will not open properly against a significantly higher pressure! If you raise the pressure more than 8-10 psi, you should have them output checked at the elevated pressure to make sure they still work ok.

Spud

Bigger injectors by themselves are no help, and probably will hurt economy somewhat. Injectors actually dribble fuel just as they open and close. Substantially larger than required will not run well at low speed. The stock ECM will run injectors up to 15-20% larger than stock and will adjust the Block Learn downwards to compensate. They engine will probably go rich when at full tilt since most of the sensors are ignored in Power Enrichment mode, and too rich, while safe, is not where maximum power is obtained. Coincidently, I pulled an early aluminum TPI manifold at the 'yard this last weekend, and it had the injectors in place. I checked the part number and they are actually .3# smaller than the LN3 injectors. I did not test the fuel pressure regulator, and they may run at a higher pressure, increasing the fuel flow. It appears there may be some confusion about the injector rating. The "pounds" rating refers to the amount of fuel they will flow at a specified pressure, not the operating pressure. Similar injectors may be used in different engines of different performance potential. The manufacturers just use a different fuel pressure setting to vary the base fuel flow. Rather than increasing injector size, raising fuel pressure a little can have the added benefit of improving atomization.