Injector Scaling Procedure

[Jordan89]

I have a '00 SS that I converter over to E85. So far, I just changed the stoich and nothing else. The car runs pretty good and everything, but since E85 requires ~30% more fuel I purchased some 42lb. Green top injectors. My question/s are:
What information is needed to scale these injectors properly?
What are the formulas that must be used to figure these things out?
Any tips?

I'm new to HP tuners, and have been reading through so many threads about this topic, but am still kind of in the blank. I know about the Greg Banish DVD, but I'm not paying $250 for one video.

[mowton]

You won't have to scale the injectors in your setup unless you run out of Maf or have extremely high cylinder loads but your setup should be good to go. Just load the correct 42 lb injector data with the stoich change for E85.

Log your fueling/inj pw and make sure they are in the safe range and you don't run out of fuel pump but again withour knowing the mods, assume its stock, you should be ok.

Ed M

Answer brought to you by someone who thought the $250 for the knowledge and injector data was well worth it. Thanks Greg, bought both

[eficalibrator]

Answer brought to you by someone who thought the $250 for the knowledge and injector data was well worth it. Thanks Greg, bought both

You're quite welcome, Ed.

BTW, Ed is also correct about not needing to scale with 42's, but this still doesn't mean you can forget about properly calibrating the tables for offset and short pulse adjust either.

[Jordan89]

The car is stock, aside from a K&N air intake. I've changed the stoich, and now I need to add the injector info. Will Greg's book be of some help for this info? I don't have $250 to spend on a DVD right now, especially after the holiday season. That's why forums are for, to help each other out. I'm just looking for guidance. Thank you guys for your replies. I'm going to look up the information on how to calibrate those tables.

[mowton]

The car is stock, aside from a K&N air intake. I've changed the stoich, and now I need to add the injector info. Will Greg's book be of some help for this info? I don't have $250 to spend on a DVD right now, especially after the holiday season. That's why forums are for, to help each other out. I'm just looking for guidance. Thank you guys for your replies. I'm going to look up the information on how to calibrate those tables.

Still believing in integrity, the injector data was developed by Greg and is contained in the 1st DVD. You take an "oath" not to divulge and I am a man of my word. To this, you can either pony up the dollars for a new or used DVD or go with LS7 injectors where you can develop the correct injector data from the 2006 Z06. Will need adapter set from a company like FIC.

The books will help alot and are very cost effective. Also the forum will help as well. check out this great collection of information.. http://ls1tuningguide.com/tuninghelpfiles.php

Ed M

[Jordan89]

Still believing in integrity, the injector data was developed by Greg and is contained in the 1st DVD. You take an "oath" not to divulge and I am a man of my word. To this, you can either pony up the dollars for a new or used DVD or go with LS7 injectors where you can develop the correct injector data from the 2006 Z06. Will need adapter set from a company like FIC.

The books will help alot and are very cost effective. Also the forum will help as well. check out this great collection of information.. http://ls1tuningguide.com/tuninghelpfiles.php

Ed M

That is a good site. Again, I am not asking for anybody to do my work, I'm just trying to gather information that will help me figure it out myself. I am not a professional tuner. I just want to be able to set my car up myself. I respect the "oath" that you have taken, just like I appreciate the help you are providing me with.

[sarg]

At what point DOES it become necessary to scale injectors? I bought and watched the dvd, but not sure when it becomes necessary. I have 160s and running a 3 bar os with a turbo.

[eficalibrator]

Any time your ACTUAL injector flow rate is greater than the maximum allowed flow rate in the PCM, you will likely need scaling. On older PCMs, this is around 8.0g/s fuel flow rate. Remember that if you are still running the in-tank regulator (no manifold referenced regulator at the rail), then the IFR table still needs to be able to model the increase in flow as the intake manifold goes into vacuum. So even if you had an injector that flows 7.8g/s (against a reference atmosphere of ~100kPa), by the time you see intake vacuum it's now flowing greater than the 8.0g/s limit and the PCM needs an accurate model to describe this phenomenon.

Also, many of the older PCMs also have an airflow limit of 512g/s (somewhere slightly north of 600hp), so hitting this limit runs into similar issues as the 8.0g/s injector limit. Chances are that if you have a very healthy engine combo that makes well over 600hp, you also have injectors feeding it that may be over 8.0g/s, so BOTH drive you toward a need for scaling. Fortunately, the scaling exercise fixes two problems at once.

[sarg]

On a 2000 camaro ecu what does that translate into for the injectors? 80lb, 100lb? I have had to do this before to work around ecu limitations with great success. Guessing around 60 lbs/hr by doing the math.

[JamesLinder]

8.0 gram per second injector limit works out to 63.49 lb/hr - the conversion factor is always equal to 7.93668 (which is equal to 3600 seconds per hour divided by 453.59 grams per pound).

[JamesLinder]

this may prove useful to some of you.

[sarg]

8.0 gram per second injector limit works out to 63.49 lb/hr - the conversion factor is always equal to 7.93668 (which is equal to 3600 seconds per hour divided by 453.59 grams per pound).

Yeah that is what I got too, but from my experience with ecus, it is never exactly what the injector might be, lol. So my thought was that 60 lbs might be a good safe limit. I guess this means my tune with 160 lb injectors and my friends at 80 will both need to be rescaled.

My next question is if this limit applies to the VE table as well or just the MAF table? Does anyone know all the various tables that need to be modified in a 411 camaro ecu?

[mowton]

Yeah that is what I got too, but from my experience with ecus, it is never exactly what the injector might be, lol. So my thought was that 60 lbs might be a good safe limit. I guess this means my tune with 160 lb injectors and my friends at 80 will both need to be rescaled.

My next question is if this limit applies to the VE table as well or just the MAF table? Does anyone know all the various tables that need to be modified in a 411 camaro ecu?

The 2000 ecu will handles cell values up to 254 lbs/hr so even the 160 injectors can be inputted. The VE limit is 519% which is quite a bit. The MAF is the sensor which is limited to 512 g/sec as well as cyl airmass (spark) max of 1.2 g/cyl which will be your limiting factor.

A Speed Density tune (VE only) would be your best bet for FI setups if you run out of MAF. MAF tune will require rapping the PE to add more fuel once it pegs (set 1500 hz to 512) and using the 1.2 cyl airmass value row for the final timing values.

In a scaled tune, what ever percentage of injector flow rate reduction was implemented, the same percentage needs to be applied to all airflow tables content/axis. Content is simple but the axis value rows/columns need to be shifted in the table accordingly. An example would be timing table---if your tune is scaled by 50% then the values of timing in the .8 g/cyl row would need to be copied into the .4 g/cyl row.

Ed M

[sarg]

So since I am going with a 3bar SD only tune at that point the only limiting factor will be the 1.2 g/cyl limitation in the ecu. At what point do these cars typically max that value out? In the other cars I have tuned I have never dealt with an g/cyl values at all to the best of my recollection. Thank you for your input everyone!

[mowton]

So since I am going with a 3bar SD only tune at that point the only limiting factor will be the 1.2 g/cyl limitation in the ecu. At what point do these cars typically max that value out? In the other cars I have tuned I have never dealt with an g/cyl values at all to the best of my recollection. Thank you for your input everyone!

Yes, you would insert the minimum timing requirements in the 1.2 g/cyl row or scale the tune. Or you can use the Spark AFR correction table to decrement the timing further. The Boost PE will be used to increase the fueling as required passed the 105 Kpa MAP value. I personally have not tune using a COS, but seems straight forward.

Ed M

[sarg]

what does the 1.2 g/cyl typically equate to in horsepower or injector flow?

[mowton]

what does the 1.2 g/cyl typically equate to in horsepower or injector flow?

It is based on Dynamic Airflow and RPM. For example if you are flowing 512 g/sec and are at 6000 RPM then the g/cyl would equate to 1.28. The equation is g/cyl = Dynamic Airflow (g/sec)/RPM*15. Not sure if that answers your questions.

Ed M

[Trevtec]

So this guy makes a Dvd for 250 and now people cant talk about anything in it making this forum nearly useless?

[doc350]

not at all.

greg spent the time and effort putting together his dvds and books. with the first dvd, he also includes injector data that he himself compiled. it wouldn't be fair to him if people just started posting his hard work all over the internet.

also, if you are really interested in tuning, and want to learn a ton about how these cars work, you should pick up the dvd anyways. they are extremely informative.

even without gregs injector data, this forum is far from useless. there is a lot of really good info and discussions posted here.

[Jabbott]

So this guy makes a Dvd for 250 and now people cant talk about anything in it making this forum nearly useless?

No, you can talk about anything you want. What would you like to talk about? In order to create this injector data you will need to purchase about 15k worth of tools and then hope to find someone to teach you how to actually create the data from the raw data which may possibly set you back another 20k. Unless you can get a job at GM and they teach you how to do it. So for $250 you get this data and it is copy righted. So not only is it an oath, but it is also against the law for someone to post it or send you a copy of it.