LSJ 60# Injector Tune with 50% Scaling

[jrsmith]

So thanks to AP83 & cobaltssoverbooster's help I believe I've got my tune properly setup for 60# injectors with the 50% scaling procedure.

First of all, I followed the guide under Link 1, except when I used the "LSJ Aftermarket Injector Spreadsheet" I set the multiplier to 2 instead of 1.3, then pasted the Injector Flow Rates in the "Flow Rate vs KPA" table as well as setting the "Flow Rate Mult vs Volts" table to 2 all the way across.

Using the numbers from the base 05 LSJ tune & following the "GM Gen IV Calibration Scaling" guide by Dave Steck; I halved the values in the MAF Calibration table "Airflow vs. Frequency" and the Main VE table "Primary". I then modified the Main Spark Advance table to adjust for the 50% reduction in airflow measurements. As an FYI, what used to be 0.64 g/cy is now 0.32 g/cl. So I basically copied & pasted from .16 to .08 and all the way up until I reached 0.68 which is half of the highest row 1.36. Above & including row 0.68 I copied & pasted the numbers from the 1.36 row. FYI, the tune i'm attaching was based off of the low octane base table which was modified & then pasted into the high octane table. This is because I'm running a turbocharged setup & I want to have a very conservative spark advance to get me started.

I then scaled the Burst Knock Retard vs. Cylair Delta table as well as the 3 DFCO tables, Enable/DisableCylAir & Entry Spark. I'm pasting a copy of my work directly below for review & I hope I didn't screw the burst knock table up!!

For the tables below, top is before, bottom is after scaling. Is there anything else that I missed? Did I make any crazy mistakes??!!!

burst knock b&a.pngDFCO Entry Spark.pngDFCO CylAir.png


Link 1: https://www.hptuners.com/forum/showt...&highlight=60s

[cobaltssoverbooster]

why would you re-scale everything..... the ecu can handle up to 126 lb/hr flow rate without table re-scaling.

i saw you post online talking about the injector dynamics file....the scaling they are doing is completely different that what the ecu does.

[Speedytec]

This 126lb/hr comes from the LSJ's 63.5lb/hr max of the IFR table with a multiplier of 2?
Thought it was found that this multiplier does not increase the max possible IFR and fuel is still capped at the 63.5lb.hr maximum...

[Area47]

you can run 60's without scaling jack shit. hell you can do it with 80's.

[cobaltssoverbooster]

i ran id1000's at 70 psi rail pressure no problem.

[AP83]

you can run 60's without scaling jack shit. hell you can do it with 80's.

I know you can do 60's, but have never seen 80's done. Just curious how one goes about this.

That is, unless you're referring to scaling just the spark tables, not the fueling and airflow.

I've always understood that the 63.5 limit is hard-coded into the P12.

[jrsmith]

Ok, so in retrospect, the tune I posted is bad because firstly I didn't actually reduce the stated flow rate by 50% to trick the ECU (should have set flow rate modifier vs Volts to 1 instead of 2), and secondly because there is no need to do this because the spark tables will never exceed 1.36 g/s with my injectors? And also I lose resolution with 1/2 the number of tables?

[cobaltssoverbooster]

the injector multiplier only scales the injector main flow rate. it modifies the base flow by multiplying whatever you have the flow multiplier set to.
so if its a mult of 1 and a base of 60 then its 60 lb/hr at that point. if its a mult of 1.5 and a base of 40 then its still 60 lb/hr at that point.
the injector multipliers, ignition, ve, etc... all remain stock when doing this.

the only reason you scale the way injector dynamics talks about is when you exceed the the table axis of the graphs in question. therefore you must first exceed the g/cyl axis in airflow before their method really comes into play.
granted you could do this if you want to but its a waste of time for anything that still flows max airflow on the stock g/cyl axis.
at 80lb/hr your still on the table.

[Speedytec]

the injector multiplier only scales the injector main flow rate. it modifies the base flow by multiplying whatever you have the flow multiplier set to.
so if its a mult of 1 and a base of 60 then its 60 lb/hr at that point. if its a mult of 1.5 and a base of 40 then its still 60 lb/hr at that point.
the injector multipliers, ignition, ve, etc... all remain stock when doing this.

But does the multiplier raise the IFR above the 63lb/hr limit on the LSJ? Several postings that say that on the LSJ it multiplies, but the maximum is still capped at this 63lb/hr...

I don't care for now, as I run a boost referenced system on my Bosch 60's with base pressure set to 43.5psi. So my maximum IFR is now ~63lb/hr, but need more in the future. Of course you can simply fit big injectors and skew the tune with the MAF curve, but it would not be "correct".

[jrsmith]

Cobaltssoverbooster says it can, so there must be some misinformation going around on the forums (shocking, I know lol). 8.00 g/s *2 = 16 g/s or 126 lb/hr

[Area47]

ifr x voltage MULTIPLIER.

[cobaltssoverbooster]

Yes just the ifr table itself is limited to 63 lb/hr. As area mentioned that table is multiplied by the ifr multiplier table to allow hight values.

[Speedytec]

That is what that multipliuer is supposed to do, but:

https://www.hptuners.com/forum/showt...ghlight=lwrs10

[jrsmith]

No, that link is talking about a completely different table, the injector offsets. Someone else can chime in about that one, I don't understand it yet.

[Speedytec]

I know it's mostly about the offsets in the LSJ ecu, but furter down:

"I have also verified the IFR voltage multiplier table DOES NOT WORK above 63.5....no matter what. The computer will only go up to 63.5....and the multiplier does not take it any farther. "

[cobaltssoverbooster]

that has not been an issue for me. again i run injectors way over what your claiming to be running and i still dont see this issue.
i know ways to tune that that most dont understand which could be why it works for me but, system rescaling doesnt help with that anyways as its not injector flow based scaling. system re-scaling is for airmass issues only as i stated in a prior post.

[Speedytec]

Good that it's not an issue then with the LSJ. As said I now run my 60lbs injectors at 43.5psi base pressure and boost referenced, so the IFR limit is not an issue yet for me. But I will need to control more injector when my 2.3 Harrop engine is ready. :-)

[Area47]

the ifr table itself is hpt hardcoded to that number, not the rest of the map itself.

[Speedytec]

Which map do you mean here? The airflow maps? (besides the fact that the HPT VE table does not much on these ecu's...)

Or some internal "fuel map" that is the result of the IFR table x voltage multiplier. etc. ?

[Area47]

if you read back years and years ago, you will find all the info you will ever need on this ecm. the missing tables, and the bandaiding need to run them. i have not touched an lsj ecm in over 2 years. i have forgotten a lot of shit since then