Help with Calc.VET on PCM Swap SBC

[spedracr93]

Hey guys - I'm looking to see if I can get a little direction from the experts so I can get on track with the Calc.VET Tuning method.

I have a 411 PCM on a 355 SBC through an EFI Connection kit. Engine has about 11:1 compression, GM Fast Burn Heads, TPIS MiniRam, 224/230 110 cam, headers no cats. Car is 89 Corvette with 6 speed and 3.92 gear. Injectors are 32 lbs. @ 43.5 and I'm running 44 psi without a vacuum pull on regulator. I'm certain that my harness is correct and my spark settings are modified properly, so I do not believe I have a hardware issue. Also, the engine has less than 10,000 miles on it and has 185 psi on every cylinder +/- 5.

Current tuning setup includes FAST WB with analog input. It reads extremely lean in most light acceleration and steady cruise situations 15 - 17, while the LTFTs are negative 11 to 18. With any quick tip in or heavy load/throttle the AFR goes way rich usually 11.2 avg., sometimes 10s. This causes the car to shudder and even give me a blinking MIL. The only thing that seems to be almost usable is the idle at 14.3 - 14.5 on the WB. With the camshaft size, I'm definitely getting reversion but I have double checked the WB with a new AFX / NGK setup and found similar results, so regardless of overall accuracy of the FAST WB, it seems to be correct.:wallbash::wallbash:

These issues seem to cause drastic spikes and holes in my Maps when trying to perform Calc.VET. I can literally have two cells next to one another at the same RPM where one goes up and the next goes down dramatically, and the cell count is high on both. I smooth the table manually, run it again and get the same results. I cannot seem to get anywhere with tuning my Main VE Table and MAF.

Given I'm running an SBC with fair duration I'm certain that the injector timing is way off but I'm not quite sure what to do about it because I cannot seem to measure any changes that I have made to injector timing.

Can I get some of you guys to possibly give my tune a look and make some suggestions that I can try changing to settings where my AFR can come more in line? I'm feeling pretty helpless with this... :help::help:

I have purchased an AEM 30-0333 with new 4.9 sensor so I can hook up Serial, but given that I have corroborated my current readings with another known working sensor I'm reluctant to install it until I get the tune more reasonable where I don't shorten the life of the new sensor.

:thankyou2:

20690

[ScarabEpic22]

Unfortunately the AEM 30-0333 will not work via OBDII with non-CAN PCM/ECMs, so you'll have to rewire it to use either analog or serial out.

I get an out-of-range for C3003 Predicted MAP Max, change that so it's not out of range.

Are you running a MAF? If you're running in hybrid VE/MAF and having these issues, try going full SD only and dialing in the VE first. Then go full MAF and dial that in. Then blend them both with a quick Calc.VET. The jagged edges of your VE table tell me there's conflicting stuff coming into your logs, VE should be nice and smooth (for the most part).

Do you have a log of this you could share as well?

[joecar]

Post log file and some screenshots of maps ( use SHIFT-PRTSCR... also see https://en.wikipedia.org/wiki/Greenshot ).

[5.7ute]

Check that you are filtering the data correctly before copy/pasting to the tune file.
Also ensure you are driving the car correctly to maximize the amount of usable data.

[Jetmech442]

Hey, reading through this I just noticed your fuel pressure is 43psi without vacuum in the regulator. Did you update the map on efilive for flow rate vs map? Stock I think for a 411 is 58 psi.

Id specify the map number, but I forgot my laptop today.

I don't want to derail the troubleshooting, so if you've taken care of it already, then carry on sir.

Sent from my Nexus 6P using Tapatalk

[spedracr93]

Unfortunately the AEM 30-0333 will not work via OBDII with non-CAN PCM/ECMs, so you'll have to rewire it to use either analog or serial out.

Yup - I built a harness to tie into the gauge to the serial port on the V2. I bought the 30-0333 because I have newer vehicles that I would like to tune some day and it will do analog, serial and can.

I get an out-of-range for C3003 Predicted MAP Max, change that so it's not out of range.

How do I change that? I have gone to C3003 entered 15 into every single cell, saved it and gone back to it and it still shows out of range. Am I missing something in that table? The highest value is 105 and I've even gone through and changed all of those to 104 and saved the file and it has still showed out of range. Is it affecting me?

Are you running a MAF? If you're running in hybrid VE/MAF and having these issues, try going full SD only and dialing in the VE first. Then go full MAF and dial that in. Then blend them both with a quick Calc.VET. The jagged edges of your VE table tell me there's conflicting stuff coming into your logs, VE should be nice and smooth (for the most part).

I am running a MAF. It's an LS2 style. When you say try going full SD, do you mean AutoVE tuning like the tutorial on the EFI Live homepage?

Do you have a log of this you could share as well?

See attached below.



20694

[spedracr93]

Post log file and some screenshots of maps ( use SHIFT-PRTSCR... also see https://en.wikipedia.org/wiki/Greenshot ).

Log file in post above.

Here are the screenshots:
20695

Take a look at the cell of 100 kPa at 400 RPMs.... That cell averaged 0.2070 with 51 counts. The engine won't even run at 400 rpms, so how did it hit that cell 51 times?

20696

[spedracr93]

Check that you are filtering the data correctly before copy/pasting to the tune file.

I think so... I'm following the tutorial that WeathermanShawn developed.

Also ensure you are driving the car correctly to maximize the amount of usable data.

I'm trying, but maybe I don't know what that is. When I log, I'm trying to drive as smoothly as possible without accelerating quickly and varying the RPMs as much as possible so as to cover as many cells as I can. That said, the majority of my cell counts are between 2000 and 4000 RPMS and 25 and 50 kPa.

Any advice to change my methodology?

[spedracr93]

Hey, reading through this I just noticed your fuel pressure is 43psi without vacuum in the regulator. Did you update the map on efilive for flow rate vs map? Stock I think for a 411 is 58 psi.


If you're referring to B4001 Injector Flow Rate, then yes, I changed that. I specified that I had done that in the original post because the TPIs and LT1s had the vacuum regulators and would therefore have a constant value for flow rate and it's a common thing that I've seen guys get wrong who have done these PCM swaps to older engines. To get the values, I used an .xls file I found on this board that spits out flow values with 3 variables: injector rated pressure, gauge pressure on rail and injector flow rate.

I am a bit concerned because I recently bought a matched set of injectors from FI Connection which are supposed to be [email protected] matched set... but they have the same p/n and look as the [email protected] set that I removed them for.

If that's not what you're thinking of, please let me know. I feel like I have gone through each and every map to make sure it made sense for my application.

Thanks

[joecar]

Sorry, I meant screenshots of the scantool maps of your logged data during the Calc.VET procedure.

~Moderator~

[spedracr93]

Sorry, I meant screenshots of the scantool maps of your logged data during the Calc.VET procedure.


Like these?

20699

20700

[joecar]

Yes.

In the map properties, for the MAF map, goto the Cell tab and constrain the cell size.

When viewing the maps, click the x-bar button to view the MAF map correction factors and the VE map calculated VE values.

In the tunetool, go Edut->Properties and set VE units to g*K/kPa.

~Moderator~

[joecar]

I'm still looking at your tune file...

~Moderator~

[spedracr93]

Yes.

In the map properties, for the MAF map, goto the Cell tab and constrain the cell size.

Thanks, that makes it much easier to read.

When viewing the maps, click the x-bar button to view the MAF map correction factors and the VE map calculated VE values.

Yup, that's how I've been plotting and modifying

In the tunetool, go Edut->Properties and set VE units to g*K/kPa.

I think I have that set correctly already. See attached map.


I feel like there has to be something in the tune that is just too far out of the parameters of the engine dynamics that needs to be improved/changed before I can really get the Calc.VET procedure to produce better results.

Have you guys ever started from scratch basically with a tune where the car just didn't seem to run right and went straight to Calc.VET? It just seems like I'm missing a critical point somewhere that needs repair before the tuning should really start. The engine ran fine with the original 165 tpi ecm, so I'm quite certain that the issue is not mechanical and I just replaced the headers (and gaskets) to be certain that I wasn't getting fresh air contamination on my O2 sensor readings.

I know that the car is running lean at normal cruise (the exhaust gas is so hot that it is discoloring the ceramic coating on my brand new headers) but it's choking on fuel with any semi aggressive throttle... I'm pulling my hair out here because I know what's going on, I just don't know how to solve it!

20705

20706

[joecar]

Try this:

set B0120 to zero (or any value below 200 rpm), this will force MAF only;

then bump up the MAF table where fueling is lean... you could use the MAF map, but be sure to apply the throttle transient filter.

sometimes it helps to start again from a stock tune.

[joecar]

BTW:

table C3003: set the out-of-range cells to in-range values as follows (there's a trick to it):

set the blue-eared cells to max-5, save file, exit tunetool (all the way out), reopen tunetool, set those cells to max value, save file.

[joecar]

...

Take a look at the cell of 100 kPa at 400 RPMs.... That cell averaged 0.2070 with 51 counts. The engine won't even run at 400 rpms, so how did it hit that cell 51 times?

It hit that cell during starting...?

You will have to edit the transient filter to exclude data engine speed is below 420 rpm.

[joecar]

If you're referring to B4001 Injector Flow Rate, then yes, I changed that. I specified that I had done that in the original post because the TPIs and LT1s had the vacuum regulators and would therefore have a constant value for flow rate and it's a common thing that I've seen guys get wrong who have done these PCM swaps to older engines. To get the values, I used an .xls file I found on this board that spits out flow values with 3 variables: injector rated pressure, gauge pressure on rail and injector flow rate.

I am a bit concerned because I recently bought a matched set of injectors from FI Connection which are supposed to be [email protected] matched set... but they have the same p/n and look as the [email protected] set that I removed them for.

If that's not what you're thinking of, please let me know. I feel like I have gone through each and every map to make sure it made sense for my application.

Thanks

Doing a calculation to sanity check your IFR table:

your 0 kPa cell is 4.0547 g/s --> this is 32.18 lb/hr so this checks ok.

your rail pressure is 44 psi (asm mentioned above) --> this is 303 kPa

your 80 kPa cell is 4.5547 g/s --> calculation says it should be 4.0547 * sqrt(383/303) = 4.5586 g/s, this checks ok.


And, your FPR is un-referenced, so your B4001 IFR should be sloped (slope goes as sqrt((300+VAC)/300)), as it does.

[joecar]

Do you have data for table B3701...?

Do you have table B9021 (defined by cax file) for Minimum Transient Pulsewidth...?
( if you have the data, see post #12 here: 17699-need-B9021-for-01250003 (https://forum.efilive.com/showthread.php?17699-need-B9021-for-01250003) )

[spedracr93]

BTW:

table C3003: set the out-of-range cells to in-range values as follows (there's a trick to it):

set the blue-eared cells to max-5, save file, exit tunetool (all the way out), reopen tunetool, set those cells to max value, save file.

That worked. I guess I had never saved then exited and opened back up before. I would save and close the window, then open the window back up.

[spedracr93]

Do you have data for table B3701...?

Yes. See attached.

Do you have table B9021 (defined by cax file) for Minimum Transient Pulsewidth...?

Nope. Must not be in my OS.


20709

20710

[joecar]

B9021 is defined by cax file for your OS 12202088...

see post #12 here: 17699-need-B9021-for-01250003 (https://forum.efilive.com/showthread.php?17699-need-B9021-for-01250003)

you rename the file "cax a.cax" to "12202088.cax" snd move the file to C:\Program Files (x86)\EFILive\V7.5\Calibrations...

then when you open a new instance of the tunetool you will see B9021.


~Moderator~

[spedracr93]

B9021 is defined by cax file for your OS 12202088...
see post #12 here: 17699-need-B9021-for-01250003 (https://forum.efilive.com/showthread.php?17699-need-B9021-for-01250003)
you rename the file "cax a.cax" to "12202088.cax" snd move the file to C:\Program Files (x86)\EFILive\V7.5\Calibrations...
then when you open a new instance of the tunetool you will see B9021.


Thanks, Joe.

I was able to get this updated in my tune but.... even after reading all of the threads on it, I still don't know what it does!

I have logged about 6 hours of data over the past week and after all of this time thinking that the car was running pig rich under throttle, I can say without any doubt that it was running pig rich, but.... it wasn't because of the tune. I had 4 burnt plug wire boots and the plugs were arcing to the headers under load. I never checked this because the plug wires are literally brand new; I put them on within the time that I've been trying to tune. I'm going to have to build my own wire set so that I can have 90 degree boots and long enough wires to turn away from the headers and then go up to the coil packs. The cool sox I had also aren't very cool anymore, so I'm going to have to get new ones and I think I'm going to wrap the primaries of the headers to help hold the heat down. The headers are ceramic but oh well.. they're brand new and already discolored from running too lean so what do I care if they get too hot under the wrap? Next I'll need a tubing bender and a tig and some inconel tubing to build my own headers....:chair:

Thanks for all of the help. After I'm back up and running (mechanically sound) I'll check back in if I'm still having trouble.

[joecar]

Be careful with misfires... when a cylinder does not fire at all, the unburnt oxygen will cause the O2 sensor to register lean (i.e. unburnt fuel does not count).


I use the MSD wires with the bendable boots.

Yes, +1 on mechanically sound, this helps tuning to go better/easier/accurate.

I found that headers always seem to discolor, my silver-ceramic coated stainless Supermaxx's have turned to a dull grey.

I think steel headers are better because they are thicker (but they rust)... stainless headers tend to be made of thin gauge tube... I wish someone would start making heavy gauge stainless headers.