Jim Cuff

I am new to HP Tuners and diving back in from my 3rd gen moates days.
Similiar just more tables.

I am going to take my car t get a pro tune shortly but I wanted to learn and get it dialed in enough to drive there.

LS1 02 trans am. rebuilt stage X 4l60 with 3200 stall and 2.73
BTR stage 2 cam
Huron v3 kit and 7875
walpro 455

I have no MAF and 2 bar.
Base tune was way off and stalled in idle/drive with no gas and super rich

I am in OLSD tune now no STFT. I have 22deg at idle and it starts right up and idles solid. 1 o2 typically reads lean and other rich at idle low RPM

Using deka file found here it ran well but still seems rich and I dialed the MINPW from the .52 to .2 it helped but still feels and sounds off.

in drive it surges at low rpm and stalls still.

I am googling and searching HP tuners but still have a few questions:

1: I will attach my files
2: in OLSD does base airflow do anything? That is only thing I have not touched.
3: I increased my idle spark form 18 to 22 and its solid. idles at 55 all day. but I didnt touch 1200+ or anything from 0-105KPA left stock. Does bigger cams need more or less spark typically off boost.
4: in boost I cut to 12 to be safe
5: in VE I added 25% in boost and 15% in vac


Anything you guys see as way off?

CyberGrey Z28

iTrader: (4)

I see a walbro 450. Are you running return system? What's your fuel pressure?

Jim Cuff

It is a returnless, inline. One part I didn’t buy. My shop handled the fuel and installed the walpro. There is no regulator in the bay or additional lines on the intake so I assume it is all stock 58bar maybe a small boost to 60psi with the inline pump.

I have been researching the hell out of the injector data and looking through the Siemens stuff and others tables. I have a few probably very dumb observations.....

1: IFR vs KPA table
I understand 0 KPA = 1 BAR right so the std flow rate at 300kps ~ 43psi = 80lbs scaled by
80*(58/43)^.5 = around 95KPA. If it was a FPR system then it stays constant, that I get.

But the KPA in this table is it Vacuum KPA? IE 0 = atm, 14.7, 1 bar then 5 KPA really is -5 KPS vac? IE 105-5 = 100 KPA ~ 14psi?

The same goes for the Battery vs Vac KPA which states VAC KPA. I am feeling it is all backwards on the data tables?

Here is my example: I am running at 50kpa at idle which reports around 7psi. Now this is 7 PSI VAC. Then as I cruised i ran up to 75kpa range and I was around 11psi with heavier stabs going to 15psi which ATM and 105bar.

So most of the tables I see they are decreasing the offset towards the 80kpa range, right side of the table. IE 80KPA ~ 60psi and using the offset for 60 psi. In reality and according to my scans, that 65-80KPA range is closer to ATM/0/14.7/1bar. Which makes sense but the tables I used showed a MS Offset for volts to vac in the 14v range of .8-.9 range. Which is the offset for 60psi pressure. In reality if should be the left side of the table or 20-30kpa numbers there? That way when in 60 KPA/80/atm range it gets closer to the 58psi values and 1.2ms offset range.

I see why people might not have noticed this since the lower values will cut fuel and people have issues with running rich. But they same issues applys to the IFR vs KPA tables. So, this might be really dumb. If 0 ~ 95 then table should be filled in at 0 then from Right to Left
80 would be the next value 97 then 70 would be 99 etc so as vac increases (-20 = 80kpa of vac) is the highest value.

This would then lower the fuel?

Second question:
Low slop/Hislope are just slopes on a graph and there is the comp for PSI for both.
This returns the IFR so I see the data tables use Bernoulli’s equation for scaling which makes sense but then there are these offsets. I would assume that only hi slope applys. Do I map the base hi slope say 80lb/hr then create a table with offsets for pressure. Do a new curve fit to get 1 straight line. Then create a new table, using the new curved fit line, for each one of the IFR vs KPA cells and compare or offset from the Bernoulli straight lines.

The Low slope I can map and the cross over of the 2 should be close to slow pulse offset value if 2.5ms. Then the low slope PSI table can be mapped against the Hi slope PSI at these points and small MS to create the knee.

The horizontal difference from the hi slope straight line, to the left of, the low slope line is the low slope offset/adder values.

The min pw in the table is 0.55 which does match the charts.

Jim Cuff

OK well I found my anwsers!

1: I was right and wrong. I spoke to FIC about my confusion on the VAC thing.
Went I presented my confusion the FIC guy scratched his head and said I was right! Then he thought about it but he said they increase the IFR values in high vac to flow less and trick/scale the injectors accordingly.

2: The VAC tables I was right, as you have less VAC you (50-80KPA) you will need more pulse. So the table values should increase from Right to Left. The tables I found had it decreasing from Right to Left!

MPW is .125 for these injectors not 0.55

Flow Rate vs Volts is all 1

CyberGrey Z28

iTrader: (4)

The walbro 450 pump will overpower the intank regulator. Injector data based off 58 psi will be off.

I've read some people tune around it but it's not the proper way to go about it. I would address that before tackling injector data.

Jim Cuff

I will check my pressure tonight and scale the IFR as needed but the new data from FIC and it worked much better.

Now I need to adjust the spark/ve/EOIT some more

CyberGrey Z28

iTrader: (4)

Do you have a wideband hooked up?

Jim Cuff

No I am going to take it to a pro tune and they will dial it in with dyno and wideband then I will install my own. I just wanted to learn tuning and get some of the basic dialed in and save some pro time.

I cut the EOIT down and WOW that was a huge difference since In sound and idle.
The stock LS has. 9.5 ATDC IVO my BTR stage 2 turbo is 5 BTDC

So 14.5 degrees and stock EOIT is 6.55 boundary
That is (14.5/15) = 0.9
6.55 -.9 I plugged in 5.58 and awesome

I played with the ECT conditions and 5.9 and 6.1 but 5.58 is the ticket.
ECT I tried adding the EVC delta but it seemed to run rich and sound worse.

I was able to lose idle and VE and fuel responded. I am seeing 02 swings lean rich and no more smell. And revs sound smooth and fast

CyberGrey Z28

iTrader: (4)

Without a wideband and being speed density your attempts at tuning are a shot in the dark at best.

Hook up an aem wideband and you'll do much better. Or tow it to a professional before you wash out your rings or go lean.

Jim Cuff

I am going to run CLSD and enable STFT. Unless it is easy to run a MAF at 7-10 lbs?

I hear you on being safe and not driving the car and Just got idle going and want to get it low/part throttle in drive working so I can get the car in and out of driveway. I was going to bring back to my shop to get EBC and some suspension stuff done so I can get a full tune from 4-10lbs dialed in.

But maybe just bring him the 4-5lb manual setup

JakeFusion

iTrader: (7)

You have to adjust your base airflow. It'll stall without more airflow.

Jim Cuff

Yes that was the 1 table I left alone as trial and error.
In park/neut it wasnt as critical but in gear I kept stalling.
I followed RK tune now and will bump up 2 and redo VE and EOIT (cross post from other EOIT thread)