I have a '91 GTA with a 305tpi and dry nitrous.

I have the stock 19lb injectors and I have gone through 2 bottles of nitrous at 75hp with no problems.....yet.

I would like to bump up the nitrous this summer to a 100hp shot.

I have been told that I am maxxing out the 19lb ers.

Should I get a set of used lt1 24lb injectors instead?
I have a afpr now, also.

LB9GTA

 

He He....i would if i were you.... later pal, GTA.....

 

You're "heads" ahead of me anyway!

 

Funny...... later.GTA

 

if you do go to a 24lb injector you will have to tune the system for the increase in fuel. i did it with mine. i also ran a 24lb inj with a dry and a wet kit. i had a hell of a time getting it set right. i prob had 20-30 dyno pulls on it trying to tune for both dry and wet kits.

 

Has anyone done this before on a 305?

Does the idle go crappy or the WOT is not as good?
Do I lose my driveabilty??

 

too much injector. you dont need to change them to a 24lb. if you are worried, then get a stock 22lb, but dont be surprised when it dosnt work that well.

 

So the driveability goes then?

 

Honestly, I think you'll be perfectly fine running a 100shot on the stock 19#'s. Should provide enough fuel.

When going to a 100shot though, you may want to swap in plugs that are one step colder (AC Delco R44TS) and run some 93 octane.

I currently have a 75shot setup on my LB9. Wish I could feel the power a bit more though. I can't really feel when it kicks in, but I can sure notice my MPH higher at the end of a nice straightaway that I always test speed on. Used to get to about 85mph on the street which is just under a 1/4 (makes sense, my trap for 1/4 was 88). With the 75shot, I was able to hit roughly 92mph, which is roughly a 7mph gain, which means that nitrous must be giving me about another 75hp

I'm running stock (leaking) 19# injectors for now but will be swapping to 24# soon. However, I'll be running an LT1 intake and LT1 heads (flowed at 221/179 @ .500") with roughly a 10.2:1 CR, CC304 cam, and 1 3/4" headers. I'll also have an adjustable fuel pressure regulator and can burn my own chips.