First time tuning an E38 from scratch

[bikewiz]

I just built an LS3 swapped Mustang drag race car and I'm trying to get a startup tune going so that I can get the car running and work out any bugs it has before I take the car to be professionally dyno tuned. I'm also trying to learn HPT so that I can confidently tune myself one day.

Here are the specs on the build:

416 ci stroked LS3, 12.3:1 CR
242/252 .629”/.629” 114 LSA +2 advance custom cam
E85 fuel
Ported LS3 heads
FAST 85 lb injectors. Return style fuel system fixed at 58psi

I started with a stock 2010 Camaro SS calibration and made basic changes from there. I've uploaded my current tune file and the log I made today of attempting fire it up for the first time.

I turned off unnecessary DTC's and made the necessary changes to run standalone. I populated the injector data tables with injector data from a ZR1 corvette because they use the "051" bosch injector which is what the FAST injector starts with before they modify it (if you read on, I found this is incorrect). I changed the stoich ratio for E85. I also scaled up the injector flow rate table from the ZR1 values (around 69% IIRC) to make 85lb/hr @ 58psi.

I've been doing a lot of reading on tuning e38's, but a lot of the tutorials and threads deal with a currently running car that has bolt ons or at the most a supercharger. I'm starting with a build from scratch that has larger displacement, higher compression, different fuel, injectors that don't come with data from the manufacturer, and a custom cam. I want to make sure I'm headed down the right path with the tuning process.

My next move was going to be failing the MAF sensor and tuning VE using Bluecat. Then I was going to back in and calibrate the MAF. In the Greg Banish Calibrated Success DVD he tunes MAF first and VE second, but as it sits the car doesn't stay running. Not sure which I should tackle first. It starts and dies after a few seconds. I think the incorrect MAF values are causing it to die and not related to any sort of VATS problem.

Can you take a look at my startup tune and offer me any pointers on what my game plan should be, or any obvious changes I should make to the tune? I'm feeling a bit overwhelmed with doing a tune from scratch in a fresh build as opposed to a tuning the MAF on a car that just had a cold air intake put on it.

Thanks in advance!

Matt

[bikewiz]

I've done a lot of reading forums the past few days an re-watched most of the Greg Banish DVD #1 again. His DVD is very helpful, but its a bit dated since it focuses on GENIII tuning. I've also been talking the mowton here on the forum for some tips on starting this tune. He suggested starting with a MAF-only tune. Many other tutorials I have found online also suggest the same thing. In light of this advice, I have come up with a MAF only calibration attached here.

I have been sidelined by frigid weather lately, but a warmup is on the way tomorrow. I'm going to take advantage of this and load this tune tomorrow after work and see if I can start playing with the MAF transfer function and plotting my lambda error.

Any advice appreciated. Thanks.

[mowton]

Looks about right for open loop, Maf only. Will need the other changes I sent you I would think. But you can start with this and see what happens.

Ed M

[bikewiz]

What changes did you send me? I don't have any messages from you. Are you confusing me with the other guy with the CTS-V you were helping?

[mowton]

What changes did you send me? I don't have any messages from you. Are you confusing me with the other guy with the CTS-V you were helping?

Turns out I had a senior moment and actually submitted the PM back to me.......sorry. here is the content of that PM.

Will continue to look into the injectors, but here are a few changes which I think should get the car running.....

1.Set idle speed min equal to target idle speed
2.Need more minimum air, multiply entire table by 1.8
3.Need more startup Airflow, multiply entire table by 1.5
4.Multiply MAF table by 1.5
5.Change High RPM Disable and Re-enable form 4000/3900 to 400/390 (will put us in MAF only, no VE intervention)
6.Set PE to 1.15 across the board
7.Set Spark Correction>AFR Correction>Gas to all 0's for now
8.Set IAT Spark>Base to all 0's for now
9.Set ECT Spark>Base in columns -4 through 212 to all 0's for now


Matt, a couple of questions...

Are there front and/or rear CATs installed? (if no rears then set all HO2S sensor 2 DCT's to no error report).
Set p0300 to no error report as well (misfire)
What Map Sensor do you have installed?

Hope this helps

Ed M

[bikewiz]

Hey Ed,

Don't worry it happened to me yesterday too lol.

No cats. Dynatech long tube headers with 3" collectors to a 3" x-pipe to 3" mufflers (perforated tube) dumped before axle. No rear O2's. I remember reading in the Greg Banish book that the tune should be compensated for the HO2S delay because I have long tube headers and the HO2S' are now farther downstream from the engine. Is this necessary at this point and how would I do that in HPT?

MAP sensor is a stock LS3 part for a 2010 Camaro. GM Part # 12591290.

I'll make those changes to the tune tonight before I try firing it up. Warmer weather is on the way so I can really start getting into this project now.

[bikewiz]

Will continue to look into the injectors, but here are a few changes which I think should get the car running.....

1.Set idle speed min equal to target idle speed
2.Need more minimum air, multiply entire table by 1.8
3.Need more startup Airflow, multiply entire table by 1.5
4.Multiply MAF table by 1.5
5.Change High RPM Disable and Re-enable form 4000/3900 to 400/390 (will put us in MAF only, no VE intervention)
6.Set PE to 1.15 across the board
7.Set Spark Correction>AFR Correction>Gas to all 0's for now
8.Set IAT Spark>Base to all 0's for now
9.Set ECT Spark>Base in columns -4 through 212 to all 0's for now

1. "Idle speed min" table was already set to 700 rpm which is the target idle speed once engine is at operating temp
2. "Airflow Final Minimum" table multiplied by 1.8. I noticed the values are different depending on what gear is selected. My setup is standalone with a TH350 trans so the computer doesn't ever know what gear I'm in. I'll have to look at what the indicated gear says in the scanner and note this so I know what values I'm actually using for idle airflow.
3. "Startup Airflow" table multiplied by 1.5
4. MAF "Airflow vs. Frequency" multiplied by 1.5
5. I already had "Dynamic Airflow Disable" at 100 rpm and "Dynamic Airflow Re-Enable" at 0 rpm.
6. Changed "Power Enrichment EQ Ratio (Gas)" to 1.15 across the board.
7. Changed "Spark Correction>AFR Correction>Gas" table to 0 across the board.
8. Changed "IAT Spark>Base" table to 0 across the board.
9. Changed "ECT Spark>Base" table to 0's in columns -4 to 212.

Going to load this tune and give her a shot. I'll update later with results and a log file. Thanks!

[bikewiz]

Finally got it running! Got flustered for an hour or so, couldn't keep it running. Had to step up idle airflow another 1.5 and and also doubled MAF freq. Finally got it to stay running and it was running very rough. Also noticed my wideband was pretty much staying at 20+ AFR on gasoline scale. I'm like WTF? After some diag, found bank 1 (the same bank that has the LC-1) has no spark. I was only running on the right bank. Turns out I have a bad MSD 2-step module. I removed that from the equation and I was running on all 8. I went back to the tune I posted above with an extra 1.5 start up airflow left in. Attached is the log of it running. I'm going to go back tomorrow and take out that 50% added start up airflow. I forgot to take it out with all the frustration from the MSD failure.

Big thanks to mowton for the help! I'll keep updating this thread and I learn the ropes and get this tune further along.

[mowton]

If it started ok, I wouldn't pull out any Startup Airflow. That just controls ETC during the startup, once it transitions to idle. Also, do you have the LC-1 configured to output AFR stoich as 14.6 or the E85 driven 9.7? You are reading 11.5sh at idle which says you are rich its set to 14.6 or lean if 9.7. That will be the MAF/Min Airflow adjustments accordingly.

Ed M

[bikewiz]

I have to throttle the pedal a bit to get it running. If I just crank it it starts and stumbles and dies. The LC-1 is still on the gasoline 14.7 scale. I am going to change it to the E85 scale I just forgot to do that when I was programming the LC-1.

[mowton]

Pull 20% of the MAF I added, looks like too much. Get AFR closer to 14.7/9.7 at idle.

Ed M

[bikewiz]

Im out in the garage now. Just got some more E85 in the tank. Used the GM fuel composition tester to verify the alcohol content on the fuel, 88.2%.

As the car sits it fires up and runs for about 2 secs and dies. I think once it transitions off the startup airflow table its cutting out. If I throttle the pedal i can keep it running. Should i kick up the values in the Airflow Final Minimum table?

I'm changing the LC-1 to E85 values and multiplying the MAF table by 0.8 right now.

[bikewiz]

Trying to log my commanded lambda and lambda error so I can start tweaking the MAF table, but every time I start scanning, the PIDs change to '<unsupported parameter>". I also went in and changed my LC-1 to the E85 scale, but readings are still the same on the LC-1 gauge and on HPT.

[bikewiz]

Need to have Air Fuel Ratio Commanded High Res listed on the table first before you can use a custom PID.

[mowton]

I'm not at my computer. Need to develop a commanded lambda PID if logging lambda.

[bikewiz]

yeah i had a commanded lambda PID made from watching the Greg Banish DVD. It uses data from Air Fuel Ratio Commanded High Res [PID.6001]. Apparently you need to add [PID.6001] on your table in your scanner config in order to use custom PIDS based off that data.

I just got it working and logged it and its saying my commanded lambda is about 0.56 and my lambda error is around 22.6. This seems way off. I think I have to re-make these pids using 9.765 as a stoich divisor rather than 14.7.

[bikewiz]

Figured it out. Greg Banish uses a Lambda input from his wideband for his custom PIDs. The LC-1 I use outputs its reading in gas AFR (14.7). So, I changed my custom PID to divide the LC-1 values by 14.7 making the readings in terms of Lambda. Now everything works like it should.

I opened the log from today with 20% removed from the MAF like you suggested and the MAF Lambda error is pretty close at idle. Need to take out another 5% or so. Just need to get some solid data populated in more of the cells to make solid adjustment to the MAF table. Multiplying the MAF table by 0.8 got me to a point where I can start the car now without touching the gas pedal for the most part. Had to help it once or twice, but its come a long way.

I'm learning a lot very quick. Thanks again Ed!

[mowton]

You are quite welcome. This forum has taught me over the years so a little pay forward is the least I can do. Glad you are getting along well on the process.

Ed M

[bikewiz]

Just a little update:

I'll be going out in the garage and working more on getting the MAF dialed in. There is snow on the ground and this is a race car with slicks on it and no license plate yet, so the best loading i will get now is the car up on the lift with the trans in gear. I know its not the proper way to MAF tune, but its better than free-revving the engine. A load bearing dyno sure sounds great right now

I did more research on the fuel injectors as I was not happy with not finding any solid data on these FAST 85-lb #30857 injectors. So, my original post has some false google search info. The ZR1 LS9 engine uses a Bosch injector labeled with #0280158187. My injectors from fast are labeled with part #0280158051 which is actually a stock LS3 injector for Corvette's and Camaro's. FAST tries to hide this Bosch part # by covering it up with a decal that is printed with the FAST logo. Luckily a few of the decals were placed crooked and I could read most of the part #. Thinking I had drilled out ZR1 injectors, I loaded all the injector data from a stock 2011 ZR1 Corvette that I grabbed out of the HP Tuners repository, and multiplied the flow rate table by a multiplier that would equate to 85-lb/hr @58psi. IIRC, I multiplied by about 1.69. As discussed before, I know the other stock injector data will change once the flow rate is changed, but since FAST doesn't supply injector data, I did the best I could.

Now, I realize that these #30857 injectors are actually drilled out LS3 injectors, I need to go back and re-load the stock 2010 Camaro LS3 injector data with the flow rates scaled to 85-lb/hr @58psi before I spend more time adjusting the MAF transfer function. I'm glad I found this info out now, rather than later on.

I hope that this info will help other people out in the future. I'm sure I'm not the only person that was suckered into buying FAST injectors because of the attractive price tag, just to find out there is no data to support them.

[HartRod]

Great thread!