Main VE table doesnt look right after scan

[mtnman]

Here's the 3-D graph of my Main VE table after 2 maps from the scan tool. Shouldnt the graph/table be smoother than this?
421

[Black02SS]

If you can post a better image of the actual 3d Graph that would be great. Also rotate it so we can see it in full.

Now, how did you adjust the VE table? Did you use a wideband and autotune? How are your BENs/LTFT/STFT after this?

[mtnman]

How's this?

422

[Tordne]

Umm.. That doesn't look good at all.

What are your BEN's or LTFTs like with that table?

[mtnman]

Here's the BEN_LC12 Average from the scan tool.

423

[Tordne]

You can email me the tune and log if you like and I'll take a look. Those BEN's indicate that the VE still needs to come down more, but the table you posted (image) just doesn't look like anything I have seen before :(.

What size injectors etc. are you running? And has the LC-1 been calibrated etc?

Cheers,

[Black02SS]

Your car is runing really rich. You need to get the bens down to .99-1.00 Also, if this is on your 2500, you need to check and make sure that the vehicel is going into PE mode. There is a table that is set to 60sec that controls this. I can't remember the table number off the top of my head.

[mtnman]

You can email me the tune and log if you like and I'll take a look. Those BEN's indicate that the VE still needs to come down more, but the table you posted (image) just doesn't look like anything I have seen before :(.

What size injectors etc. are you running? And has the LC-1 been calibrated etc?

Cheers,

Email sent. The injectors are stock injectors for an '03 2500HD although they have been flow-matched.

[TAQuickness]

Notice the ~ 15% richness... I imagine this is from one of the steps in the AutoVE tutorial that fattens up the VE table so you don't blow your motor during the process.

[Tordne]

Your car is runing really rich. You need to get the bens down to .99-1.00 Also, if this is on your 2500, you need to check and make sure that the vehicel is going into PE mode. There is a table that is set to 60sec that controls this. I can't remember the table number off the top of my head.

I got the tune now so I'll have a glance over all that.

[Tordne]

Do you happen to have the stock tune for this vehicle? I don't seem to have one on my tune repository. Looking at your injector flow rate table it looks "very strange" and could likely be your problem.

[mtnman]

No, the stock tune that came with the truck is long gone. I'm pretty sure that the tune i'm working off of is from the list of tunes provided on the EFILive website(2004_Chevrolet_Silverado_6.0_4L80E_stock.t un).

[mtnman]

The injector flow rates for all my different tune files seem to be the same (25.236 lbs/hr for all values in table).

[mtnman]

If you can post a better image of the actual 3d Graph that would be great. Also rotate it so we can see it in full.

Now, how did you adjust the VE table? Did you use a wideband and autotune? How are your BENs/LTFT/STFT after this?

Innovate wideband and autotune. I have not returned to closed loop SD, since the table values in the scan tool havent been 1.00 yet. I've just been going back and forth between the BEN_LC12 table in the scan tool and the Main VE table.

[Black02SS]

Innovate wideband and autotune. I have not returned to closed loop SD, since the table values in the scan tool havent been 1.00 yet. I've just been going back and forth between the BEN_LC12 table in the scan tool and the Main VE table.

Hop onto AIM if you have a min.

[joecar]

I think possibly you may have to double check your IFR table using the IFR spreadsheet available from http://www.allmod.net/hpt/injectors.xls

[Tordne]

The injector flow rates for all my different tune files seem to be the same (25.236 lbs/hr for all values in table).

This is the only tune I have seen like that. Check out a tune for say a 2002 Camaro and see what I mean. The IFR table is usually calculated and will be be a linier line, as opposed to a flat line.

That will have an effect on the values that are required in the VE table to get a correct AFR.

I would be inclined to use the link that 'joecar' posted and calculate the IFR table to what I believe it "should" look like. Then take your stock VE, increase by 10% and start again.

[joecar]

Oh wait, he has a truck, so it may have a MAP referenced fuel pressure regulator, so your IFR table would be flat (no slope)...

In this case use this formula to check your IFR table:

NewFlowRate = SQRT((NewPressure + BARO) / RatedPressure) x RatedFlowRate

NewPressure is the static pressure (no vacuum applied) that the FPR is set to;
to measure this, install gauge on front of fuel rail, pull the vacuum line while engine runs, read gauge.

Edit: Check also that the vacuum line to the FPR does not leak.

[Tordne]

Oh wait, he has a truck, so it would have a MAP referenced fuel pressure regulator, so your IFR would be flat (no slope)...

In this case use this formula to check your IFR table:

NewFlowRate = SQRT((NewPressure + BARO) / RatedPressure) x RatedFlowRate




OK, didn't know that gem :master:

[ZL1Killa]

i gaurantee that you are running rich....

that looks like a stock VE table except for what you have lowered there.
(it looks like my stock VE table)

if you already got a wideband and got it correctly setup in efi live scan tool go for the VE dial in and hit a lot of cells ...if you don't have the MAP set up I can send you my MAP of the Benfactor(dial in VE) for the PLX wideband(LM-1&LC-1 if you set it up the same as the PLX voltages...more accurate)

let me know if you need some help....i pretty much just finished my speed density tune and got my VE table dialed in

[mtnman]

I think possibly you may have to double check your IFR table using the IFR spreadsheet available from http://www.allmod.net/hpt/injectors.xls

Are the flow rates on this table for stock injectors? I have no idea what the injector rated fuel pressure, fuel rail pressure, or injector rated flow rate are. How do I find these values out?

[joecar]

You use this spreadsheet if you have a non-referenced fuel pressure regulator (no vacuum line, located in tank), goto A.

If you have a vacuum referenced FPR (located on fuel rail), as most/some trucks do, goto B.

A.Non-referenced FPR
In the spreadsheet you enter your injectors rated flow and rated pressure
to get these values, search web using the part number printed on your injectors (this is the hard part);
you then enter the fuel rail pressure (measured using a gauge);
the spreadsheet computes the injector flow rate curve for vacuum ranging from 0 kPa to 80 kPa (vacuum is BARO - MAP);
copy the column of values having the same units as your IFR table, and paste onto your IFR table.

B. Vacuum referenced FPR
Use this formula to calculate the single value IFR:
NewFlowRate = SQRT((NewPressure + BARO) / RatedPressure) x RatedFlowRate
(use the same flow rate units as your IFR table)
Paste this value across your whole IFR table.


Edit: here's a site that shows some ratings for various injector part numbers:
http://users.erols.com/srweiss/tableifc.htm
goto the Bosch and GM sections.

[joecar]

You have to remember to use consistent units as you calculate;
to convert lb/hr to g/s mulltiply by 0.126.
(1lb = 453.6g, 1hr = 3600s)

[joecar]

Are the flow rates on this table for stock injectors? I have no idea what the injector rated fuel pressure, fuel rail pressure, or injector rated flow rate are. How do I find these values out? You have a truck, check to see that you have a FPR on the fuel rail:
a can with a vacuum hose and two fuel lines (supply and return);
if you see this use method B;

if you see a can on the fuel rail without a vacuum hose,
then that's the pulse dampner and not the FPR.

[joecar]

If you post your injector part numbers, someone may know where to find their rated values.

[mtnman]

A.Non-referenced FPR
In the spreadsheet you enter your injectors rated flow and rated pressure
to get these values, search web using the part number printed on your injectors (this is the hard part);
you then enter the fuel rail pressure (measured using a gauge);
the spreadsheet computes the injector flow rate curve for vacuum ranging from 0 kPa to 80 kPa (vacuum is BARO - MAP);
copy the column of values having the same units as your IFR table, and paste onto your IFR table.


Do i have to measure the fuel rail pressure using a gauge or is it the same for all stock GM 6.0liter engines? I dont have a gauge and I've been trying to find information on the web do give me this number, no such luck yet.
Also, I've been trying to find the "injector rated fuel pressure" and "injector rated flow rate" and havent found anything. I looked at the table and found the rochester/GM injector numbered 5235401 and I've used this in a search and found nothing.:bash:

[joecar]

mtnman,

So is 5235401 is printed on the side of your injectors...?
You have to jump up on your engine an eyeball all around the nearest injector.
Unless your vehicle is stock it's hard to know what's in there.

I don't know what fuel pressure the 6.0 engines use, is it 58 psi...?
You can look up the service manual for your vehicle to get the fuel rail pressure,
althgough an EFI fuel pressure gauge cost less than $40 and can come in handy later when diagnosing problems.

If I missed it, what vehicle year/model is it, it is upto 2003 I may be able to look it up...?

Cheers
Joe

[mtnman]

mtnman,

So is 5235401 is printed on the side of your injectors...?
You have to jump up on your engine an eyeball all around the nearest injector.
Unless your vehicle is stock it's hard to know what's in there.

I don't know what fuel pressure the 6.0 engines use, is it 58 psi...?
You can look up the service manual for your vehicle to get the fuel rail pressure,
althgough an EFI fuel pressure gauge cost less than $40 and can come in handy later when diagnosing problems.

If I missed it, what vehicle year/model is it, it is upto 2003 I may be able to look it up...?

Cheers
Joe

I'll check the number on the injectors tonight to be sure.

I'll look through the service manual for the fuel pressure.

[joecar]

mtnman,

Also, see if you can see the FPR;
it should be located on one of the fuel rails,
and it has 2 fuel lines attached (supply and return), and also a vacuum line;
if it doesn't have these 3 attachments, then it's not the FPR (it'll be the pulse damper);

you need to know this so you know to use method A (sloped IFR) or method B (flat IFR) mentioned previously.

Cheers
Joe

[Delco]

It really doesnt matter if your inj flow rate is miles of , it a multiplier to the VE table so in the interum go and do lots of logging ( you have only done a small amount of area from the snapshot you provided and the VE table has been modified accordingly.) worst case if your IFR is 15% out then the VE table will be 15% out to compensate - the only real thing it causes is the dynamic cyl air to be out of cal.

If you find your peak Ve's are a long way from 90-105% then multiply your IFR table by the % required and modify your VE up or down by the % and then go and redo your auto tune again.

Get the whole table populated and not just with 1 or 2 hits then apply it to the VE table , you will find your whole VE needs to come down a lot

[kbracing96]

His truck should have the vac ref pressure reg on it. They didn't go to a returnless system in the trucks till 04. IFR should be set to 25.4 across the board. It looks to me like he added the 15% to the VE table which on my truck was WAY to much and had similar results. Should probably go back to the stock ve table and mabey bump is 2-3% at most I would probably leave it stock and then auto tune from there. My ve table was pretty close from GM.

[mtnman]

It really doesnt matter if your inj flow rate is miles of , it a multiplier to the VE table so in the interum go and do lots of logging ( you have only done a small amount of area from the snapshot you provided and the VE table has been modified accordingly.) worst case if your IFR is 15% out then the VE table will be 15% out to compensate - the only real thing it causes is the dynamic cyl air to be out of cal.

If you find your peak Ve's are a long way from 90-105% then multiply your IFR table by the % required and modify your VE up or down by the % and then go and redo your auto tune again.

Get the whole table populated and not just with 1 or 2 hits then apply it to the VE table , you will find your whole VE needs to come down a lot

The light green cells are the results of 50+ cell counts where coolant temp is above 178 degrees. I didnt use any cells values that had a count less than 50

[mtnman]

It looks to me like he added the 15% to the VE table which on my truck was WAY to much and had similar results. Should probably go back to the stock ve table and mabey bump is 2-3% at most I would probably leave it stock and then auto tune from there. My ve table was pretty close from GM.


Yes, I did bump up the values by 15%. I'll try the stock values or a lower percentage.