As requested since I can be called a pro from all my issues lol. Figured I would post here so everyone can have it.

How to swap out fuel injectors:

Tools:
10mm deep socket
3" or 6" extension (whatever you find first)
Ratchet (whatever drive you have the socket and extension in, I use 1/4 drive)
Flat head screw driver (small one)
Rags
Fairly big towel
Safety glasses
Silicon grease

Step one:
Take the cap off the schrader valve. Put your safety glasses on. You will be depressing the pin in there to release the fuel pressure. Put a rag around the screw driver and SLOWLY push this pin in. It is a good idea to have the glasses on because the fuel can squirt anywhere. Once this is fully depressed and the hissing stopped you can replace the cap and move to step two.

Step two:
Now take off the 4 10mm bolts that hold the fuel rail to the manifold.

Step three:
Now we have to take off the throttle cable. I have traction control so I only have one line going to the TB, I cannot comment on the set ups without traction because I haven't taken one appart. You have to CAREFULLY pry the plastic tab back just enough to slide the clip out. Once you get the cable out put it up on the cowl screen to get it out of the way. Now disconnect all the injector connectors by pushing the metal bar in on them and pulling up. I also unplug the EVAP plug and the plugs for the coil packs. I take out the TB and IAT and MAF plugs too and get all the wires out of the way. Take the flat head screw driver and open the wire holders on the fuel rail. They are little black circular clips, one side you can insert a screw driver to open it up.

Step four:
Now you have to pry the injectors out of the intake. I usually grab onto the front and jiggle it and pull up at the same time. I keep my hand steady on the intake manifold while pulling up to prevent me from pulling too much. You just want to "pop" these out and be careful not to pull too far. I like to start from the front and work my way back. Once you get all the injectors out of the intake, snake the whole assembly out, being careful not to snag one of the injectors on something.

Step five:
Once you get the rail out (I believe there is a braided line under the rubber so dont be scared to move it around, I wasn't) turn it upside down and lay a fairly big towel under the whole fuel rail. There are little clips that hold the injectors in. Take a look at how these hold onto the rail and injectors so you will know how the should look reinstalled. Pop these out using a flat head screw driver on the back side of the clip, slide it in and twist, keeping your hand there to keep the clip from dropping. Take out all 8 and set them aside.

Step six:
To remove the injectors from the rail, I use a small circular rotation while pulling up. They will eventually pop out and fuel may come out too from shaking it so just be careful. Get all 8 out. On the new injector o-rings you want to put some sort of silicon grease, be sure to get it on the oring only, on both of the orings, not doing this may damage the orings. Use the same technique to reinstall the injectors except push towards the rail gently. You can see little grooves in the injectors. This is where the clip goes and just below this point on the clip is a slot, that is where the fuel rail holds onto the clip. Be sure these are all properly clipped in place. Reinstall all the clips and injectors.

Step seven:
Now you want to reinstall the rail, snake it back through again watching that the injectors don't get stuck on something. Once all the injectors are partly seated in the intake, depress them in the rest of the way. Plug all the connectors back up and clip everything in place. Now put the screws back in to hold down the fuel rail, these are the 4 10mm bolts. You want these snug, not tight. Now put your TB cable back on.

You will have to tune the injectors now, as for me, my car runs really bad. Apparently all you have to do is change the IFR table. 98/01/02 all come with 28.8# injectors stock, 99/00 come with 26.4# stock. Take your injector 4 bar rating and divide it by the factory:

in my case, i have 38# racetronix injectors that flow at 43.65# at 58 psi

43.65/26.4=1.6534

I then multiplied the IFR table by 1.6534 to get the proper numbers. I am having idling issues right now but it seems that this works for everyone else.

Start your car now, check for leaks, if all is good take the car for a spin and see how it works. Hopefully none of you will have my issues, most prob won't seeing noone else on this board has a clue. Must have some bad injectors or something, I don't know. I have idle problems, hunting idle. If you don't have this problem good. If you do PM me if you know how to fix it haha.

If I left anything out let me know, which I have done this.....7 times now trying to fix my problem.

 

This will help me TONS when I install my 42s do you know what I should times the table by? I think I have the 26.4s?

 

who makes the injector? what is the 42 rated at?

 

it is also the racetronix 42s let me get u the details:
Static Flow Rate: 42.29 lb/hr @ 43.5PSI (300kPa) or 320gm/min
Static Flow Rate: 48.83 lb/hr @ 58.0PSI (300kPa) or 370gm/min

 

1.8496 is what it needs to be scaled by. let me know how those injectors work out for you. i cant get mine to idle worth a damn

 

I will let you know I will prob install on the 7th of next month because I am really busy but I will def let you know

Thanks For all of your help!!!

 

42# racetronix worked great on my buddies car. I think his had trouble idling the first minute or so after he cranked up but now its just like normal.

 

this may seem like a really silly idea... or perhaps its a great idea.... but.



theres only so many injectors out there... is there any reason everyone couldnt just post their injector tables along with any other changes they have made??
that way someone like me could go, hey, i just got these 40lb injectors, and with the stock fuel pressure, i just set my table to this ____??

for example, this is mine:
stock 2002 Fbody
stock fuel pressure

if someone could post up the same thing for their injectors, along with any other changes needed for thoes injectors to operate correctly, we could get a little database going here that would help everyone.

 

good idea, i'll make some tables for the popular ones. i have data on stockers (28.4,26.4, 28.8), racetronix of course has their data on the site. does anyone have _precise_ data on the SVO ones?

 

Thanx for the write up!


Mototron 60# RaceTronix rated
<<<<<<<Static Flow Rate: 60 lb/hr @ 43.5PSI (300kPa) = 630cc/hr>>>>

How would I convert these flow numbers to 58 PSI???


EDIT:
Using HP Tuners Unit conversion calulator they would flow

69.28 lb/hr @ 58 PSI

My IFR multiplier would then be 2.4 correct???

 

60*sqrt(4/3)=69.282 is your new rating at 4bar
69.282/28.8=2.4056 is your new IFR multiplier

 

Thanx RedHardSupra!

 

yeha use the number redhardsupra gave u, more decimals themore accurate it is. im talking with ken at hp tuners to figure out my problem i will post the results. maybe we can make this the official injector thread, cause i know a lot of people do this and we can have all info about tuning and install in here.

 

well, i looked up a bunch of "stock" bins online and double checked them on other stock bins...

this is the stock injector table for Fbodys:

now i just need the common aftermarket injector tables.

 

i have a spread sheet for injectors if someone can host it, its great

 

to be honest about it, i dont trust any spreadsheet...

the numbers for what XXX injector truly flows could always vari slightly from ideal...

since all of the fueling is dependant upon these injector constants, id want them to be as accurate as possible... meaning id rather have a table for this set of injectors that someone has idling on their car perfectly...... know what i mean?

 

yea, but how are you gonna know that? you wanna flow every injector?

WS6FirebirdTA00: i can host it, but i also wanna precalculate a bunch of popular ones so people can just save it as a gif on their puter and use it without extra programs.

 

o yeah i understand popular ones but look at this

i have racetronix 38# injectors. my tables are like everyone elses but im having trouble getting mine to run right. at least with this table you can get *about* where it should be and then dial it in from there. once i figure out how to get my stuff situated ill post up in the first part of this explaining the rest of what i had to do. but this way you can get a base IFR table for your injectors. which personally i want to use the right table for all of this because the difference in injectors is the same on stock, i would make other changes and trust the manufacturers flow numbers. thats just my opinion though. our stock injectors could be different but we have the same tables and our cars seem to act the same brand new. get what im saying

 

not EVERY injector.... but i want to see what works. in otherwords if you have 60# mototron injectors and you use this table... and then 3 other guys post their tables, we can see whats working.... that way when someone else comes along and has a table that looks very diffrent, he knows somthing isnt right.

in otherwords, no, not flow every injector, but have a list of what people are using and what works... like the HPtuners BIN database...

ideally though, yea, i would flow my injector at diffrent fuel pressures to get the flow numbers... athough i dont see that happening anytime soon.. lol.


post it up in the forum as text too.. for us copy/paste folk.. lol.

 

see a lot of people have the 38# injectors listed in their tables as 31#ers, i dont like to tell my computer a false injector size to get it to work, i want it to knwo the right one and then fix the computer to work with that