Check sig for engine details, I was wondering if my stock injectors are 19lb or 22lb. I was also curious as to what is the largest injector I can go to without having to reprogram my chip. My car is MAF if that helps.

 

Stock 350 injectors are 22#/hr. If you think you need a little umpf, install a AFPR. What is your reason for upgrading your injectors?

 

Best way to find out what Injectors your car has since thirdgens all have quite a bit of history behind them is to run the numbers, *** knows what on our cars has been swapped by previous owners.


they CAME as 19 on 305,s and 22's on 350's

 

I spoke to Rich at Cruzin Perf. this morning he verifyed they where 22lb. I dunno, since my motor is all stock I think a good cleaning session and flow testing will be good for them. I think I have some leaking which is causing my car to be extremely hard to start. I am going to pull them sometime soon and send them to him to have his cleaning and testing done on them.

 

My stock 22#'ers are leaking kinda bad... I dont know if I should just get my 22#'ers cleaned and flowtested for the new ZZ4 going in or if I should just go with 24#. I don't wanna reprogram my chip, but because I will have new motor, runners, base, and tranny, I will probably need to anyway. Guess I should go with the 24# in that case, huh?

 

Stock programming will tolerate the modest increase from 22 to 24 if you keep the fuel pressure at stock 43 PSI or a little less, but don't get to thinking "if 24s are good, then 30s must be better!." Doesn't work like that.

 

Good point Damon, bigger is not always better. I have been thinking about just buying some 24lb injectors so that way I can save time swapping them out. I can not seem to find some good 22lb injectors for sale. I guess it would be a good idea to also pick up an adj fuel press regualtor so I can adj the press down some. Does anyone know of a good place to get 22 or 24lb injectors? Has anyone ever bought any off of ebay?

 

I bought some off ebay from bruce@fiveomotorsport.com for $115, They are supposed to be 21lb injectors. Mine were leaking and I put on an AFPR at the same time. These seem to work fine and were cheap, though now I think he sells them for $145. But I know he is still selling them so you could email him and find out the particulars.

 

Okay, I think I have figured out what I am going to do. I am going to get some 24lb injectors off of ebay since there are lots of them on their and most the people selling them have very positive feedback. I am also going to buy an AFPR. I figure since I will have everything off to do the injectors, that would be the best time do it. I also bought a profession fuel press gauge kit so I can adjust it and get it dialed in right. The next thing, in the near future is to buy some chip burning equip and start diving into the world of DIY chips.
What da ya think?

 

I would just stick to your stock injectors. I really dont think that a stock motor is going to benifit at all from larger injectors. The AFPR is a great idea. I have one and with a nice scan tool you can really get your car running right. Also everyone that says just bump up your fuel pressure and you will increase HP is not right. I actually went lower on my pressure when I put in my AFPR because I was running rich at stock psi. I would say keep your eye open here for some 22#ers and then send those in to be cleaned. That is what I think I may be completely off.

 

Thats what I would like to do but I can not find any 22lb 'ers anywhere. I realize right now I may not benefit a whole lot but the question is, can I run the 24lb injectors for now and just turn down my press with the AFPR? A scan tool is something else I would like to add to my arsenal of tools in the near future. Can you find scan tools on ebay or does anyone ever sell used ones on here?

 

The easiest way is if you already have a laptop just buy the cable and see if someone would send you the software. You can do the afpr w/ 24#ers and turn it down but to really be able to tell what it should be at is by hooking up a scan tool. Well I guess you could tune it by nose and just keep turning it down until you dont smell gas but you still may be running rich. Unfortunetly it is really up to you on what you are going to do. Unless you have a build up in the near future then just deal with it until then.

 

You can drop the fuel pressure down to around 38-39 psi and it'll be close enough, if your AFPR will let you run that sorta pressure. The best way is to change the constant in the chip though.

As for what a stock ecm will 'tolerate' as far as injectors are concerned, it wont tolerate anything. Running a different flow rate than what its programmed for will throw the fuel curve off. You might get away with 2-3#/hr different and the car will still run and not spill raw fuel out of the tailpipe, but its extremely far from an ideal situation.

 

Thanks for the info guys. For right now I guess I will try to get a good deal on some 24lb injectors for now and the Holley AFPR. It does go down to 35PSI so I should be okay. You are right madmax, it wont be the ideal situation until I can go into the chip and change the injector constant. There was a guy who posted from 22lb injectors on the classified board but he has not written me back yet. As far the scan tool goes, I have a P 75mhz laptop with like 8mb of ram and a 200MB HD. I have Win95 B on it right now. Does anyone know if that would be enough to run the scan tool software? What all will the scan tool software tell me?

 

Depends on what scan tool software you get. Craig's free stuff (which I am too stupid to get to work, apparently) is DOS based, same with Diacom. I have Ease, which is windows based and does run on 95A and 98 for sure, so it should work fine on 95B. Basically it'll tell you what the o2 is reporting for rich/lean conditions and various other data some of which is important and some of which is trivial.

Changing the injector constant is so easy its not even funny. It'd be nice if some of us could push a button and just change it for ya over the phone

 

Thanks for the info Madmax. I just got my Holley AFPR a few days ago from Summit. It looks good but the plastic has been opened and someone install the vaccum fitting on to it. It looks like all the parts are there and are in good shape. It just kinda gets me PO'd when I drop $79 for the thing and almost $8 for shipping and handling just to buy a part that someone returned. Hopefully it will be okay. I am planning on pulling my injectors this weekend to send this off to Rich at Cruzin Performance.
I am trying to sell another car I have right now so hopefully with the profit I am going to buy the prom burning equip and maybe a set of headers.