Need Fuel Injectors Data Fast 46lbs

[Alex5.0]

Hi ,

I have a 2500hd Silverado , 421ci stroker LQ9 , AFR head , 228/235 Comp cam , comp RR , Fast intake , Fast TB and Fast 46lb injector .

I did nt found any info on this forum .

The engine was running great with the holley EFI software while the motor was on engine dyno but in the truck it run like crap and they bring me to make it run smooth . Before starting the tuning I would like to have this info .

Thanks

[mowton]

What PCM and what year?

FAST injector data is very hard to find but my limited understanding of the 46# units is they are a direct replacement for an LS2 (i.e 2005 corvette). You use the FAST IFR data (readily available on the internet and the rest of the LS2 parameters like OFFSET, SPA, min pulse etc.

Hope this helps

Ed M

[Alex5.0]

OS : 12212156 2002 w/4L80e

I just did a small log and with the IFR of 46.x I have to cut 50% on the entire VE Table and run like crap , if I keep the stock value I add almost 50% everywhere . I would not play with the IFR to have a 'normal' VE value .

Thanks Ed

[mowton]

OS : 12212156 2002 w/4L80e

I just did a small log and with the IFR of 46.x I have to cut 50% on the entire VE Table and run like crap , if I keep the stock value I add almost 50% everywhere . I would not play with the IFR to have a 'normal' VE value .

Thanks Ed

I'm not sure where you are starting from....How was the truck tuned before you got it? Can you post a tune and any logs you might have.

Ed M

[Alex5.0]

It was not tune when it came here, PCM was stock . I start the tune from scratch .

The shop who build the engine put it on a dyno , and they used a Holley EFI pcm with the harness to make a couple of pull to break in the engine . Then they put the engine in the truck with the new build trans and a TCI 3500 w/lockup converter .

[Alex5.0]

I called Fast , they told me those are Bosch injector 0 280 158 049 which are OEM #12569113 . They told me too with there software they don t need any specific data .

Those OEM injectors are rated @ 34lb/58psi so how fast can make them flow at 46lb ...

[nkautz]

Just because the injectors flow 46lb/hr doesn't mean you set the IFR to 46. Start with a stock tune for your ECU year from the repository and adjust entire IFR table by a % until your idle fueling is reasonable, then tune MAF / VE

[mowton]

Just because the injectors flow 46lb/hr doesn't mean you set the IFR to 46. Start with a stock tune for your ECU year from the repository and adjust entire IFR table by a % until your idle fueling is reasonable, then tune MAF / VE

What? If the injectors flow 46 then that is the data you use!

Ed M

[Alex5.0]

I put my hands on a Ford 42's , I ll give a try tomorrow . I will not take all my night to try to find useful data .

[mowton]

I put my hands on a Ford 42's , I ll give a try tomorrow . I will not take all my night to try to find useful data .

That is a good option. It is also why I only use injectors that have Greg Banishes data or Injector Dynamics with their great data. Saves a lot of time and headaches. There are a few other units I have data on but only use if absolutely necessary.

Good luck with the Green Tops, will go much easier.

Ed M

[gagliano7]

I don't understand how these company's can sell injectors and not give you the proper data. Its not like you are buying something cheap.

[mowton]

I don't understand how these company's can sell injectors and not give you the proper data. Its not like you are buying something cheap.

Actually, that is how they get their business. Their injectors are cheaper than the "Data Guys" and modders are always looking to save a buck......sometimes in the wrong area. :-)

I would like to add, and know there are some who will flame me, but have also had good success with John from Fuel Injector Connection .

Ed M

[Alex5.0]

FAST answers me that those injectors works nice with there EFI systems and no needs for data to use FAST EFI . Call Bosch for anymore information . Bosch said this part was built OE for GM. The only spec listed by Bosch is listed below. Please contact GM directly for further assistance.

Flow rate 3-bar/min 213.0 g
Resistance 12.0 Ohm

No I will not call GM loll , I feel like im in a Asterix and the twelve task cartoon ...

[mowton]

PM sent

[jim2092]

I called Fast , they told me those are Bosch injector 0 280 158 049 which are OEM #12569113 . They told me too with there software they don t need any specific data .

Those OEM injectors are rated @ 34lb/58psi so how fast can make them flow at 46lb ...

That OEM # is indeed the injectors that are in a 2005 C6. (on my work bench right now). The injector data (E40) will be available from the tune repository but as you know, may not match your ECM. tables. I would not think these are big enough for your cubic inches.

[nkautz]

The reason why I wouldn't put 46 in the IFR table is because the injectors flow rating may have been at a different fuel pressure than what your car's fuel pressure is. That's why it's easier to adjust the IFR until fueling is close enough and then continue tuning. I've tuned 32lb - 80lb injectors referenced FPR and non-referenced , the stock offset and short pulse tables have been fine in every instance. It's generally just the IFR , minimum pulsewidth , and transient min milligrams that needs adjustment.

[LSxpwrdZ]

IMO ditch the junk and get something worth a hoot.

As for adjusting IFR until AFR is accurate is the WRONG way to do it. How can you manipulate injector flow rate based on AFR when the airflow model that is telling the PCM to match fuel to is also wrong? You have two unknowns that you are trying to use to adjust the known data. Any constant is just that, a constant. Lie to the PCM and it will lie to you back 100% of the time!

[mowton]

IMO ditch the junk and get something worth a hoot.

As for adjusting IFR until AFR is accurate is the WRONG way to do it. How can you manipulate injector flow rate based on AFR when the airflow model that is telling the PCM to match fuel to is also wrong? You have two unknowns that you are trying to use to adjust the known data. Any constant is just that, a constant. Lie to the PCM and it will lie to you back 100% of the time!

^^^^^^ Agree 100%, by the way just an update, Alex got a set of Green Tops and all is well with the world again :-)

Ed M