What is the stock # of PPH for the injectors on an LO3? Also, do you know what the stock fuel pressure is normally set at, from the factory? Thanks!

 

The stock fuel pressure varies from the factory from 9psi to 13psi. My "91" RS is factory set at 12psi as you can see from this Summit fuel pressure gauge I installed.

 

I am pretty sure the stock injector part numbers vary from year to year, but...

this is an old question and has a few answers listed under this link.

https://www.thirdgen.org/techbb2/sho...ighlight=chart

 

So, from the specs I have 40 PPH injectors in my LO3? And going to the HOLLEY TBI bumps it up to 57 PPH injectors. Confirm this please.

 

I believe the stock injectors are 40 pph. The holley 670 does come with 57 pph injectors. It works great. Just give your ECM time to catch up.

 

What do you mean by give your ECM "time to catch up?" Thanks!

 

essentially the ecm is constantly adjusting what it knows about your engine via the 02 sensor to give it a better esitmate of how much fuel it should be letting through the injectors.

if you change injectors etc it will take a while for your ecm to relearn how much it needs for fuel

those are the simple terms if you want to know more, find info on blm and integrator numbers.. do a search.

 

I still have the stock injectors on my eng so unless you're adding alot more mod's or CI you don't really need more. FYI I have also tried the LO5 cop car injectors on this set-up and it was way too rich.

 

I have 350 injectors for my setup, will they be too much and what fuel pressure should I set them at

Ported World S/R torquer 305s
Edelbrock TBI manifold
ZZ4 cam (208/221 .474/.510 112)
slp headers
highflow cat
3" catback

currently:
305 injectors @ 11.5psi
slp headers
highflow cat
3" catback

 

You'll have to try them and see IMO. I could not turn the psi down low enough to not be running too rich and tried the 305's and they worked fine. I only installed the 55lb injectors because I was advised that I would need them. And I had them on hand. In your case you will be trying more cam and you might need them.

 

DM91RS... What psi are you running your injectors at? Also how much hp do you think you are making.

 

The psi varies from 10.25 to around 11.5. Why it varies this much I don't know but I do have an electric in dash guage to keep a check on it.

As far as how much power the thing is producing....I'm not one going to make a quess on that....which is all it would be. I believe dyno printouts or 1/4 mile speeds would be the only way to determine that with any accuracy.

I don't know if a G-teck is accurate or not. I've got one but havn't used it since the cam swap. It showed 93-94 mph if I remember correctly and from what I've read those numbers are usually high to actual 1/4 mile times.