timing table maxed out?

[ryans1000]

I am flowing 1.5 grams/cyliner and my timing table b5913 only goes up to 1.2 g/c . I'm assuming that is fine and that the 1.2 timing column is just applied to anything over 1.2 g/c ?

[joecar]

Yes, that is my understanding, applies to all edges of all tables.

[dc_justin]

On a side note, how much boost are you running to see that much air mass?

[ryans1000]

Boost is set to 6psi but its about 35 degrees outside now and the boost will spike up to 7.5psi sometimes. The 1.5 g/c airflow was made at the 7.5psi. If I had to take a wild guess I would say that the car feels like it has around 450whp. Still tuning and timing is pretty low. Feels about like when I had a 100 shot on the car last year just comes on smoother, perhaps a bit more horsepower now but less torque then the 100 shot. My non-intercooled setup brings the IAT all the way up to 150 degrees sometimes even when its 35 degrees outside!

[dc_justin]

Boost is set to 6psi but its about 35 degrees outside now and the boost will spike up to 7.5psi sometimes. The 1.5 g/c airflow was made at the 7.5psi. If I had to take a wild guess I would say that the car feels like it has around 450whp. Still tuning and timing is pretty low. Feels about like when I had a 100 shot on the car last year just comes on smoother, perhaps a bit more horsepower now but less torque then the 100 shot. My non-intercooled setup brings the IAT all the way up to 150 degrees sometimes even when its 35 degrees outside!

I really think there is something else "off" in your tune, as you should be closer to 1.05 g/cyl with an LS1 at 6-8psi, not 1.5g/cyl. That air mass indicates that you have VE table values that are in the 130-140% range, which is not realistic. Perhaps your injector settings are incorrect? IFR values that are significantly too high would cause VE table values to be way too high after tuning.

For reference, a procharged, 8psi 427 conservatively putting out 660rwhp (mainline dyno, not an inflated dynojet) only saw around 1.35g/cyl at peak.

[ryans1000]

I really think there is something else "off" in your tune, as you should be closer to 1.05 g/cyl with an LS1 at 6-8psi, not 1.5g/cyl. That air mass indicates that you have VE table values that are in the 130-140% range, which is not realistic. Perhaps your injector settings are incorrect? IFR values that are significantly too high would cause VE table values to be way too high after tuning.

For reference, a procharged, 8psi 427 conservatively putting out 660rwhp (mainline dyno, not an inflated dynojet) only saw around 1.35g/cyl at peak.

Yes my boost ve table is still being dialed in . At the 1.5 g/cyl I was commanding 11.28 afr but was seeing 10.18 afr at 155kph @ 5600rpm. That VE cell was at 132% and it will be at about 119% after I make the correction.

I did see another guy on here with a Twin Turbo M6 LS1 dyno 537whp. His Max was 1.37g/cylinder .

[ryans1000]

You have me concerned though as I did just install new injectors and something unexpected happened. I installed my 60lb mototron/seimens injectors and updated my injector tables according to the Greg Banish cd (IFR, minimum pulsewidth, small pulse threshhold, small pulse adjust table, pulsewidth table) I was surprised to find that I was running 10-20% lean in most load conditions from 30kpa on up. This is open loop, speed density. I had previously had my VE table dialed in good and my previous injectors were just stock and so was I had stock injector tables except for the IFR I flattened out because I have a boost referenced regulator.

I am confused as to why my ve table needed so much adjustment, I thought most areas would be within a few % afr. I did not buy flow matched injectors but I was told they are usually within 2-3% from the manufacturer.

My FPR is boost referenced and is before the fuel rail, stock fuel rails. I set it 58psi at zero vacuum. Setup hasn't changed from when I had stock injectors.

What do you guys think?

[5.7ute]

Does your regulator increase the fuel rail pressure under boost? If it doesnt then the VE table will need to be raised to overcome the inaccuracy of the fuel model.

[ryans1000]

yes my rail pressure gets pulled down into the 40's somewhere (i forget) under vacuum and under boost it rises 1:1.

[dc_justin]

You have me concerned though as I did just install new injectors and something unexpected happened. I installed my 60lb mototron/seimens injectors and updated my injector tables according to the Greg Banish cd (IFR, minimum pulsewidth, small pulse threshhold, small pulse adjust table, pulsewidth table) I was surprised to find that I was running 10-20% lean in most load conditions from 30kpa on up. This is open loop, speed density. I had previously had my VE table dialed in good and my previous injectors were just stock and so was I had stock injector tables except for the IFR I flattened out because I have a boost referenced regulator.

I am confused as to why my ve table needed so much adjustment, I thought most areas would be within a few % afr. I did not buy flow matched injectors but I was told they are usually within 2-3% from the manufacturer.

My FPR is boost referenced and is before the fuel rail, stock fuel rails. I set it 58psi at zero vacuum. Setup hasn't changed from when I had stock injectors.

What do you guys think?

That signifies that your injector settings are definitely not accurate. You should have to make no change whatsoever to the VE table with a change in injectors as you have not made any change that fundamentally alters the engine's ability to act as an air pump.

On the same token, any load point with over 100% efficiency, especially 119%, is highly unlikely.

[mr.prick]

Which PID are you using to log grams/cyl?
I ask because the MAF based CALC.CYLAIR does not match exactly when
I compare it to GM.DYNCYLAIR_DMA.
Probably from imperfect MAF values, altho AFR/BEN is near perfect with MAF only.
I've not compared GM.DYNCYLAIR_DMA to GM.DYNCYLAIR tho.

Here is the IFR spreadsheet for logged fuel pressure.
InjectorsFromFP.xls (http://marcintology.com/tuning/InjectorsFromFP.xls)

[Highlander]

dc justin is right... check your IFR settings.

[SSpdDmon]

I've found that a stock MAF curve and a 100% MAF tune is the easiest way to dial in IFR. If you use data for when the injector is in a fairly linear operating range (usually between ~5ms and ~10-15ms), you can get a decent understanding of where the line needs to be drawn in the IFR. Then for the lower flow rates, you can adjust the other injector tables to dial in the right commanded IPWs. Not having to play with the MAF curve too much saves time for me and keeps the grams/cylinder in check too so you're not flying off the timing map so much.

Once you get the IFR in check with the stock MAF curve, you can pull the MAF and dial in the VE. Seems kinda backwards, but that's what worked for me.

[joecar]

He said he was good on VE, and then he changed injectors and injector tables, and now I take it his BEN indicates lean...

(I don't know if he's running with MAF...?)

So logic would point to the changed tables, as said above...

(also keep in mind he has a manifold-referenced FPR, so his IFR will be flat across...)

That's a large difference that cannot be credited to the other (non-IFR) injector tables (would you agree...?), so this points to the IFR itself being out...

Questions for you Ryan:

- did you measure rail pressure with reference hose disconnected (58 psi you said)...?

- does it stay steady as you rev/load the motor (with hose off)...?
Call this BPB "base pressure at BARO".

- with reference hose connected, do you observe that this relationship is maintained:
gauge pressure at rail = BPB - BARO + MAP = BPB - MANVAC
where BARO would be approx 100 kPa or 14.5 psi at sea level.
use same units for all quantities (all kPa or all psi)...
use this to convert BARO and MAP from kPa to psi: http://www.onlineconversion.com/pressure.htm
Get some rail pressure readings for different MAP values and post them.
e.g. in psi:
58 psi - 14.5 psi + 30 psi = 73.5 psi
58 psi - 14.5 psi + 100psi = 143.5 psi
58 psi - 14.5 psi + 106 psi = 149.5 psi

- when you used the spreadsheet to recalculate the IFR did you enter in the correct flowrate and pressure in the correct boxes...?
Post your spreadsheet.

- and then did you copy/paste the correct value into B4001 (with the correct units as indicated by B4001)...?

[joecar]

Does your MAP sensor handle above 100kPa...?

[joecar]

...

That's a large difference that cannot be credited to the other (non-IFR) injector tables (would you agree...?), so this points to the IFR itself being out...

...Is that entirely true...? Maybe not...

[5.7ute]

Is that entirely true...? Maybe not...

Under WOT conditions, where his high readings are the other injector tables wont have much if any effect, so I would agree. I would be wondering how accurate the injector data was for his original tune before reading much more into it.

[ryans1000]

That signifies that your injector settings are definitely not accurate. You should have to make no change whatsoever to the VE table with a change in injectors as you have not made any change that fundamentally alters the engine's ability to act as an air pump.

On the same token, any load point with over 100% efficiency, especially 119%, is highly unlikely.

Well I'm pretty confident that I have my 60 lb injector values entered properly . I just don't know why my old injectors settings would be wrong since they were stock injectors and stock settings just IFR flattened for my boost referenced regulator. So I guess I'm just trying to figure if my regulator setup is causing the off settings.

Also I understand what your saying about 100% efficiency but if you look at the OS3 tutorial instructions , for the boost VE table the instructions say to take the 105kpa column in the main ve table, paste it to the boost ve table's 105kpa column . Then for the 285kpa boost ve column take the 105kpa values and add 300%. Then fill in linear values for kpa between 105 and 285 . Then tune the boost ve table from there. So by doing this your going to have ve values way above 100% . In fact at 285kpa my boost ve table shows some values near 300%

[ryans1000]

To answer all your questions. My IFR b4001 table has a value of 9.242188 in every cell (Injectors are called 60lbers at 43.5psi but in reality they usually flow about 63lbs). I am not running a MAF although I could install one temporarily but I'd rather not. Yes I have a gm 2 bar map sensor. I am logging GM.DYNCYLAIR_DMA for airflow. I am running operating system os3 with Open loop speed density.

I will have an in dash fuel pressure gauge installed tonight so I will take some readings under boost. I appreciate the help, this issue is bugging me.

[dc_justin]

Well I'm pretty confident that I have my 60 lb injector values entered properly . I just don't know why my old injectors settings would be wrong since they were stock injectors and stock settings just IFR flattened for my boost referenced regulator. So I guess I'm just trying to figure if my regulator setup is causing the off settings.

Also I understand what your saying about 100% efficiency but if you look at the OS3 tutorial instructions , for the boost VE table the instructions say to take the 105kpa column in the main ve table, paste it to the boost ve table's 105kpa column . Then for the 285kpa boost ve column take the 105kpa values and add 300%. Then fill in linear values for kpa between 105 and 285 . Then tune the boost ve table from there. So by doing this your going to have ve values way above 100% . In fact at 285kpa my boost ve table shows some values near 300%

Which injectors specifically are you using and what do you have for your settings? I can assure you that if you changed only the injectors and IFR table(s) and are seeing the things that you are seeing that the flow rate table is absolutely inaccurate.

The tutorial will yield a VE table that is VERY much higher than actual. For example, my own personal 9psi LQ9 (will have higher g/cyl than your 5.7L due to displacement and pressure) sees a peak of about 92% in the boost VE table, with very very similar values in the 115kPa column as in the 155kPa column.

[dc_justin]

To answer all your questions. My IFR b4001 table has a value of 9.242188 in every cell (Injectors are called 60lbers at 43.5psi but in reality they usually flow about 63lbs). I am not running a MAF although I could install one temporarily but I'd rather not. Yes I have a gm 2 bar map sensor. I am logging GM.DYNCYLAIR_DMA for airflow. I am running operating system os3 with Open loop speed density.

I will have an in dash fuel pressure gauge installed tonight so I will take some readings under boost. I appreciate the help, this issue is bugging me.

If they are the 63.2lb/hr at 43.5psi units, then they flow right around 72.3lb/hr at your 58psi of differential pressure (these: http://www.racetronix.com/L107.html). Your IFR value of 9.242188 would be very close to correct for those injectors at 58psi then. Your fuel pressure would have to be significantly far off for it to cause your VE table to swing out by 10-20% (greater than 15psi off). Hopefully your FP gauge will be revealing there.

[ryans1000]

I just did a little driving with my new in dash fuel pressure gauge. Looks like my fpr does rise at a 1:1 ratio correctly. I did find that my new gauge reads about 3-4psi lower then my under hood gauge. Pressures are being read from the same location.

So if my old ve table with stock injectors was tuned with this lower pressure (54psi instead of 58) what would that do? And would the ve error be worse once the 60'lbers were installed?

[5.7ute]

So if my old ve table with stock injectors was tuned with this lower pressure (54psi instead of 58) what would that do? And would the ve error be worse once the 60'lbers were installed?

Tuning with the incorrect IFR due to lower than calculated fuel pressure will give you the inflated VE table values you are seeing.

[ryans1000]

dc_justin: can you post some of your logs and tunes. I'd just like to see them to try to learn a thing or two and compare. You seem to be good at knowing how one change in one table will effect another table. What formula are you using to know how much a change in IFR will require a change in a ve cell?

[5.7ute]

Ryan, look through here to get an insight of what is going on. http://redhardsupra.blogspot.com/2006_12_01_archive.html
Using Marcins (RedhardSupras) methods you will be able to sort out your tune fairly quickly.

[dc_justin]

I just did a little driving with my new in dash fuel pressure gauge. Looks like my fpr does rise at a 1:1 ratio correctly. I did find that my new gauge reads about 3-4psi lower then my under hood gauge. Pressures are being read from the same location.

So if my old ve table with stock injectors was tuned with this lower pressure (54psi instead of 58) what would that do? And would the ve error be worse once the 60'lbers were installed?

That 54 vs 58psi would yield only a very minor error, around a 3.5% difference, not the 20-30 you are seeing. What is your wideband situation?

[ryans1000]

I have had a new aem wideband this whole time with both injectors. Not sure if its accurate but it seems to behave properly (goes rich at wot, reads stoich around idle) Would comparing the wideband to the narrowbands around stoich be a good way to test?