Tuning CUSTOM E40 ECM boost VE table with lesser injectors!

[Mr teabags]

Hi, very new to efilive, have purchased the v2 unit and have been reading the forum pro furiously
Months now .Trying to gain enough exp and knowledge to make my own adjustments :Eyecrazy. My tune
Was done professionally several years ago made over 1000 rwhp S /C with the suited injectors at that hp. Currently now the vehicle is de- tuned with a s/c air intake restriction and smaller injectors ,maffles,open loop Sd tune .Now reading efilive posts and looking at most tune files on forum I notice that VE tables usually increase air as map and rpm increase . Looking at my table I note that at the higher map /rpm areas my table values
Become lesser. Would this be due to having smaller injectors that would run out at higher boost levels?
Can you trick the ECM by scaling down the V/E table when you have not enough injector flow at high Rpm.
My objective would be to change injectors , re- do VE , timing and so on

[ScarabEpic22]

You should just re-scale the injector tables including IFR, pulsewidth, voltage offsets and if the VE is close, it shouldn't require much more than a quick touch-up of the VE tables.

[Mr teabags]

Hi Erik, thanks for the response . I am very new to efi -live slowly learning through the forum and hopefully understanding enough
to have the confidence in applying what I learn to my own vehicle. My engine is highly modified running a vortech v7 SC. It was
tuned by one of the best that was at the forefront when efilive started. The ecm is an e40 with the boost table , originally it was tuned
with the 1000cc rc injectors with a driver ( for max HP ) but being a street car the most efficient injectors at the time for street duties were the Siemens Mototron 60lb/h and that's what is currently being used. Currently I have an air intake restriction prior to the SC
air intake due to I think the injector is not large enough. If removed it has delivered 20-22 psi with the correct injectors . hopefully one
day I wish to put bigger injectors and remove the restriction and re- map the required tables . I believe im running OLSD tune without the maf .
your response is a little confusing to me , the car runs and idles quite well I'm trying to get my head around my tune esp the air tables .

[joecar]

Do you know these things:
- what is the flowrate of your new injectors (and at what pressure are they rated...?)...?
- what is your rail pressure (measure with manifold reference hose removed)...?

If you put the correct injector flow rate into table B4001, then your previously tuned VE table should still be quite close, as Erik said.

[Mr teabags]

Hi Joe , I am slowly understanding this tunning ( efilive ) as I progress and hopefully understand I become more excited. I am still
waiting for my plx W/B serial conversion with the TTL converter board to arrive its been about 4weeks and still waiting for delivery . I cant wait to have all my pids logging correctly and then making the correct changes to my tune .
Firstly I would like to really commend you on the support you provide to all that are new to this forum , without your help we prob
would be screwed . At the moment I'm screening my current tune and coming to terms with the table values ( why and how ) .
- what is your rail pressure (measure with manifold reference hose removed)...? It is prox 58psi ( but does flexuate a tad )
what is the flowrate of your new injectors (and at what pressure are they rated...?)...? I have not decided on injectors but I would need
injectors suited to around 1000 rwhp . Would you recommend any with all the data and have excellent idle characteristics?

I have attached the data from the siemens deka 60lb/h that is currently in my tune.

[joecar]

...
Firstly I would like to really commend you on the support you provide to all that are new to this forum , without your help we prob
would be screwed .Thanks :)


At the moment I'm screening my current tune and coming to terms with the table values ( why and how ) .
Here is some reading that will hopefully explain how the GM PCM's determine fuel/air: https://forum.efilive.com/showthread.php?14188-Summary-Notes
Note that your E40 ECM is GM's transition from the LS1 P01 (part # 0411) PCM and the LS3 E38 ECM... so it has features/tables/pids from each.



It is prox 58psi ( but does flexuate a tad )

The GM Service Manual states that 58 +/-1 psi is acceptable.


I have not decided on injectors but I would need
injectors suited to around 1000 rwhp . Would you recommend any with all the data and have excellent idle characteristics?

I have attached the data from the siemens deka 60lb/h that is currently in my tune.
Try to get injectors for which there is established data, not just the flowrate, but also the boundary condition data (like small pulse flow).
I believe the Siemens Deka 60 lb/hr have established data, there is a data sheet floating around somewhere.

Huge injectors will idle just fine if the small/minimum pulse flow data (and a few other parameters) is all correct (sometimes may have to run a lesser rail pressure (so scale the IFR table to this rail pressure).

[Mr teabags]

You should just re-scale the injector tables including IFR, pulsewidth, voltage offsets and if the VE is close, it shouldn't require much more than a quick touch-up of the VE tables.
Hi Eric , I just understood what this response meant. I now have more reading to absorb, obviously with an over-temp brain.:book: