FiTech Injectors?

[village_idiot]

I had a customer drop off a vehicle with FiTech injectors in an 04 Avalance with the factory PCM. I'm not too keen on attempting to tune it with them in it, but I could be wrong. What I have so far...

Part number on the injector is 222701631-5

After being on hold for 30 mins, the FiTech tech support rep told me the "-5" means they are 36# injectors, and then emailed me a "data sheet" that looks like garbage to me. Is there a way to convert it to make sense in HPT language?

Should I just throw them in the trash?

I'm attaching the data he sent...LS Injector Specs -5 -6.xlsx

[5FDP]

Good luck, they are only good for FI-Tech system. Tell the customer to get injectors with data that can be used with HP Tuners.

[RDF1]

Ive thrown away a whole bunch of FI-Tech junk.
Your better off just buying injectors with known data unless you want to spend a good bit of time fooling with those.
Or try some flex fuel 36# data and see what happens.

[Alvin]

You just have to try something close and go from there. I haven't had to give up on a set of them yet.

Honestly having injector data is a relatively new thing in tuning.

[Darkblood]

Has there been a solution to this ? I've also been handed this broken Spreadsheet from Fitech. No clue what I'm supposed to do with it. Does anyone have a running Tune with these fitech injectors ? I have the 55LB ones.

[TheMechanic]

Nope, no solution. Had a set put in by a customer and attempted the data given. Turned out it was at 43 psi. Called Fitech. They gave me new data. Gave it a try. Still ran like garbage. Used data from a few different places based on the number. Still no luck. Finally fixed the issue by using a set of new GM 412's with the data from Blindsquirrel and never looked back. I will not do programming if they have Fitech injectors. The are overpriced garbage.

[realspeeddan]

I need to replace a set of Fitech "36 lb" injectors with something that has good data available.
The injectors are very short, about 38mm between the o-rings, with the old jetronic/EV1 style plug.
I will rewire the harness to use the newer style plugs if I need to.
If someone could point me in the right direction, like maybe which factory GM vehicle has that length injector so I can buy the injectors and pull the data out of a factory calibration, I would appreciate it.

[blindsquirrel]

innjector dimensions.jpg

GM Gen4 Injectors v2.0.xls

19421333 - 29lb various Gen4 trucks (alt# 12580681)
12587269 - 33lb LY6, L76
12580426 - 35lb @58, 33lb @51 L59 (alt# 88894361, 89017586)
12594512 - 36lb LMG, LC9
12613411 - 38lb LMG
12576341 - 42lb LS3
12609749 - 50lb L92
12613412 - 51lb L96
12598646 - 52lb LSA, LS9

[obthomas]

You just have to try something close and go from there. I haven't had to give up on a set of them yet.

Honestly having injector data is a relatively new thing in tuning.

When you do not have injector data do this:

1. Find out the rating of the injector. This is a rated pound per hour at a rated presure. My injectors are rated at 42# at 60 psi. I used to have some that were rated 30 psi at 60 psi. This rated information is the easiest to find.

2. Go to the HPT fuel flow vrs pressure table and erase all of the flows. Insert your rated flow at your rated pressure.

3 go to HPT unit conversions and use the injector calculator to get more flows at the pressures in the flow vrs pressure table. Populate the entire table.

4 If your rated pressure data is outside the flow vrs pressure table read up on scaling.

This will be straight up correct unless the injector manufacturer has different information as a result of actual testing.

[blindsquirrel]

Flow rate is all you need (or not even that) if all you want it to do is WOT. Have fun dialing in the part throttle manners without any of the Offsets & Short Pulse Adder data.

[obthomas]

I had a customer drop off a vehicle with FiTech injectors in an 04 Avalance with the factory PCM. I'm not too keen on attempting to tune it with them in it, but I could be wrong. What I have so far...

Part number on the injector is 222701631-5

After being on hold for 30 mins, the FiTech tech support rep told me the "-5" means they are 36# injectors, and then emailed me a "data sheet" that looks like garbage to me. Is there a way to convert it to make sense in HPT language?

Should I just throw them in the trash?

I'm attaching the data he sent...LS Injector Specs -5 -6.xlsx

Look at the spreadsheet and note that there are 5 tabs along the bottom. Each tab is for a different injector and contains the rated flow and pressure in pounds per hour at bars of pressure. When you click on an injector tab up comes test data at different pulse lengths for that injector. Most of this data would not be used by the average tuner. Just take the rated flow and rated pressure and go to the HPT unit conversion tool, injector calculator and calculate flow at all the pressures in the fuel vrs pressure table.

[obthomas]

Flow rate is all you need (or not even that) if all you want it to do is WOT. Have fun dialing in the part throttle manners without any of the Offsets & Short Pulse Adder data.

Injector offsets and pulse adders are wonderful when you have them. They make a great topic for another conversation.

[blindsquirrel]

The topic is 'injector data needed for the stock PCM', what the hell would the other topic be that only deals with offsets & SPA?

[obthomas]

The topic is 'injector data needed for the stock PCM', what the hell would the other topic be that only deals with offsets & SPA?

I know, We could call it injector offsets and injector pulse adders.

[SiriusC1024]

If it's a street vehicle, offset and SPA are going to be pretty important for the guy who is running 55lb injectors.

[blindsquirrel]

Who gives a shit about the proper way to calculate the flow rate?

You can get any unknown injector to do WOT rips just fine without even changing the flow rate, or by plugging in a best-guess. Just do whatever's needed to the VE/MAF, doesn't make a whole lot of difference to anything if it's off by a bunch from reality on these airflow-based systems, especially if it's a manual trans. (try that on a torque-based Gen 4 with an auto trans and let me know what the total repair bill is afterwards, would be good for a laugh anyway.)

If you want to use aftermarket injectors that don't come with GM-format data, then that's easy to solve too. Use an aftermarket ECU.

[Darkblood]

wow. so theres really no nice way to translate Fitechs info to use on a regular P01 ? I guess Ill have to sell these then. I agree with the previous statements.. these are 55LB, and this will be a street driven vehicle, so offsets and SPA are needed.

I've re-emailed Fitech and see what they come back with. I doubt I'll get anything back from them considering everyone else's responses on here. lol

[blindsquirrel]

This shouldn't really be any more unexpected than what you'd get if you asked FiTech for data to use their injectors with a Holley ECU. Or going to the Ford parts counter and asking them what is needed to use Ford injectors in your Dodge. FiTech injectors work just fine with FiTech EFI systems, I imagine. They're not universal injectors.

[Alvin]

wow. so theres really no nice way to translate Fitechs info to use on a regular P01 ? I guess Ill have to sell these then. I agree with the previous statements.. these are 55LB, and this will be a street driven vehicle, so offsets and SPA are needed.

I've re-emailed Fitech and see what they come back with. I doubt I'll get anything back from them considering everyone else's responses on here. lol

Best guess would be to pick a injector that has data that looks and flows like the one you have. This is a hack but should get you closer than using stock data..

For instance. FAST branded 33's.. sure do look and seem like LS2 injectors.

[Darkblood]

Best guess would be to pick a injector that has data that looks and flows like the one you have. This is a hack but should get you closer than using stock data..

For instance. FAST branded 33's.. sure do look and seem like LS2 injectors.

Yea I actually tried this using injector data from Fuel Injection Clinic. I tried using their 540CC 60lb injector data since the flow was very similar to what fitech supplied... but had no luck.
I also Tried using Deatschwerks 50LB data with no luck either.