So I swapped a 411 ECM with O/S 12212156 into a 97 Z28. The car fires and idles but runs like a dog and has horrible throttle response. I've adjusted as much as I can possibly think of so far but it feels like I'm chasing my tail. Any help would be appreciated. Here's a copy of the tune. My biggest question is about the injector data because that what feels really off. I know the LT1 is FPR so it's a flat IFR but does the offset or pulse have to changed as well? Thanks in advance.
9.hpt
RAW Racing in Tampa, Fla.
Providing custom LS tuning and performance upgrades.
If this your LT1 (SB2) file, The firing order [ECM]14000 is incorrect, Your Firing order is 18436572, not 18726543 unless you did a cam change. Injector Bank [ECM]12301 is wrong for a LT1 Inj Bank Sel1 LS.png Inj Bank Sel2 SB2.png.
That was quick look. Did you rewire the injectors?
The VE must be tuned. It's drastically different for those engines and will look a lot flatter than anything your used to seeing.
GEN 2 LT1's will take minimum 32 degrees at WOT up to 42 degrees at WOT. you have 24.. That's timing you might run with say 15 psi of boost.. just giving you some reference.
Tuner at PCMofnc.com
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What Alvin said exactly. Even the factory Vortec 350s are dogs running the OEM advance curve. Put a little timing into them and they wake up, get alot better mileage and run cooler. On 91 octane I run a pretty aggressive advance curve in the Vortecs. On E85 almost no curve. On E85 mine loved 34 degrees at 2,400 rpm. I gained 20 ft/lbs peak to peak at the wheels and lowered the peak 500 rpm on E85. At 2,600 where it made peak on E85 it was up nearly 35 ft/lbs at the wheels. 295 vs 330 ft/lbs @ 2,600.Originally Posted by Alvin
Last edited by Fast4.7; 12-15-2022 at 02:17 PM.
Did you swap the wiring for injectors AND coils 7/4 & 3/2?
1997 30th SS. Torqhead 24x, TFS heads, 223/235 cam, 4l80e, S60 D1SC 14psi
The coils where rewired to match the LT1 firing order, the injectors weren't.
RAW Racing in Tampa, Fla.
Providing custom LS tuning and performance upgrades.
Swapped the coils but not the injectors.
RAW Racing in Tampa, Fla.
Providing custom LS tuning and performance upgrades.
Ok I get that. I neutered the timing to see if that was my issue. I was crossing things off my list, I'm most concerened that my injector data is wrong.
RAW Racing in Tampa, Fla.
Providing custom LS tuning and performance upgrades.
One of my next steps was going to be tuning is SD, I've tuned these swaps before and never had the current problems I'm having. I usually go SD on anything earlier than a LS3. I took a bunch of timing out just in case so I wouldnt hurt the motor while trying to figure out what's wrong.
RAW Racing in Tampa, Fla.
Providing custom LS tuning and performance upgrades.
YUCK! Speed Density is terrible compared to MAF/Speed Density blend. Honestly MAF only runs better than Speed Density and it is easier than Speed Density even. The only time I would ditch a MAF is when it becomes a limitation on a boosted setup.
Injectors wiring needs to be swapped as well. Its there only true way to change the firing order.
1997 30th SS. Torqhead 24x, TFS heads, 223/235 cam, 4l80e, S60 D1SC 14psi
Honestly.. you are so low on timing that you'd start causing issues.
I disagree with this.. But to be fair we are all entitled to our opinions.
Tuner at PCMofnc.com
Email tuning!!!, Mail order, Dyno tuning, Performance Parts, Electric Fan Kits, 4l80e swap harnesses, 6l80 -> 4l80e conversion harnesses, Installs
Well I will say it this way. I have been tuning for 18 years. I have gone through all kinds of builds, platforms, speed density, MAF only, blended, MAF with OEM widebands, and even some ECMs that are purely injector pulse width vs map vs rpm tables (MEFI & JTEC). I have even tuned the EEPROM based Magnetti Marelli controllers the Edelbrock MPFI systems came with 10+ years ago.
You can dial in your VE table however you want to and disable the MAF. I will select MAF only at 400 rpm. I will be done setting up a MAF transfer function in 30 minutes to 1 hour using wideband and fuel error percentages while you play with the VE tables for hours or even days. I will have better drivability, better throttle response, more consistent fueling and better MPG.
I actually first dial in the MAF if it even requires any changes, then once it is close, I data-log using a histogram table a large portion of the VE table straight from calculated VE data using MAF, MAP, IAT, and Cylinder volume math and filtered data settings. I can take that data input it into the VE table, hand fill and blend in the untouched cells with some ballpark numbers fairly quickly. When both the VE and MAF are working together the engine runs even better than running one or the other exclusively.
I laugh every time I see an open loop speed density tune on anything that does not have like 70*+ of cam overlap. Even with something like a 236/248 @ 0.050 on a 108 LSA I still use MAF and Closed Loop. I will open loop idle, but when the engine starts to breath and overlap effect becomes minimized it is back into closed loop. Going down the highway at 2,000-2,500 rpm the cam above has no issue in closed loop.
I will say I am not a fan of the MAF setup on the LT1 and L31 Black Box factory PCM setups. Then again I think a 90-92 TPI 7730 and a 93-95 TBI truck PCM are superior to the LT1 or Vortec Black Box computers and those were simple speed density. The early OBD2 PCMs were so lagged by the weak processor and complex OBD2 emissions routines I find a swap to a P01 or P59 instantly makes those engines run ALOT better. The 93-95 TBI truck PCM was easy to run a GM MAF on with port fuel injection. GM fixed the reason I am not a fan of those L31/LT1 PCMs with the P01s and P59s.
In a non-emissions application, ditching the emissions code for EGR, Catalyst overheat, canister purge and the like in the 93-95 TBI PCM to make room for code changes. 2-3 bar MAP sensor with VE and Spark Tables to 8,000 rpm. The NA section had 5 KPA resolution, the boost area had 5 KPA resolution with a 2 bar and 10 KPA resolution with the 3-bar. The injector current sense resistors could be bypassed to eliminate the Peak and Hold function so that standard saturated port fuel injectors could be driven.
The hardware could also be easily altered to provide batch fire port fuel injection rather than the TBI injector firing sequence. It also controlled a 4L60E or 4L80E natively. I was able to activate an IAT/MAT with fuel and spark compensation. The PCM could also control an electric fan and electric water pump or a/c compressor clutch. I also wrote code to control water/methanol injection and for a different setup Nitrous with Nitrous retard and PWM Nitrous solenoid control.
That PCM had multiple unused inputs and outputs available depending on the setup it was running which gave the ability to control additional hardware. This was the first PCM I added a wideband signal directly into the datastream on. I even wrote code for Wideband Closed Loop that worked extremely well. Controlling the nitrous solenoid, it could even turn the nitrous off if the wideband started to drift lean or the knock sensor activated. The nitrous code I wrote also interacted with the transmission code and would momentarily shut off the nitrous during a transmission upshift.
Very capable PCM if you have the ability dissect, reverse, read and to write the Motorola Assembly code it operated from. I also ran a Northstar DIS system with that PCM 15+ years ago to convert a turbo LT1 away from Opti-Spark, hence the code modifications. The code I wrote for the DIS, Turbo LT1 had some cool features as well. It controlled a GM boost solenoid and also had wideband closed loop. The boost solenoid would cut boost if the IATs rose too high, the wideband started to go lean or the knock sensor was triggered. This one had the Water/Methanol control. None of that was meant to bypass sound tuning, rather help prevent engine damage if possible.
The best part is with a Moates AutoProm and TunerProRT I could datalog and real time tune the things 15+ years ago. I was spoiled to that setup and found having to stop and reflash the OBD2 stuff very time consuming. I should have bought a Moates RoadRunner when they were available, but I still have TunerCats OBD2 in addition to my HPTuners.
I am also now using Universal Patcher/Table Seek. It is great for editing .BIN files for P01 and P59s. Far more of the calibration is visible and adjustable. Want Flex Fuel in a P59 that did not have it, add it no problem. Want Lean Cruise, no problem. Need to alter the file to run a gauge cluster from serial data, it has it covered. I currently have a L31 based 383 with a P59 running a 4x Distributor Igniton, Flex Fuel, Lean Cruise, Serial Data Cluster, Analog Cycling AC, and an EV Fan clutch.
If I had alot more free time, I would dive into the P59 code on my own. The controller has so much potential for customization beyond the 1, 2 and 3 bar speed density operating systems offered. I know the MAF code could be rescaled to provide far more than 512 gm/sec of airflow allowing full use of a LS3/LS7 cartridge MAF. I also know that the cylinder air load values could be rescaled to provide accurate timing control with more boost. I know the PCM physically still has the linear EGR inputs and outputs as well as other undocumented inputs and outputs. I would disassemble one of these PCMs and really trace out the internal circuits that are connected to every pin. It would be cool to incorporate column mounted paddle shifting of a 4L60E or 4L80E fully manually. I think it could also be configured to talk with a 6L80/6L90 TCM as well with the right changes. As they were created, they communicated with the Allison TCMs.
Last edited by Fast4.7; 12-19-2022 at 01:56 AM.
Wow.. cool !
Tuner at PCMofnc.com
Email tuning!!!, Mail order, Dyno tuning, Performance Parts, Electric Fan Kits, 4l80e swap harnesses, 6l80 -> 4l80e conversion harnesses, Installs
I’ve played with Universal Patcher during couple of months now. Even send some $$$ to Jouko, the developer.
I didn’n know, though, that lean cruise can be activated but of course it is possible… will try that next summer.
I am VERY interested in lean/cruise mode... I have it on my 411 pcm but I have heard on this forum it isn't in operation. My big block sucks fuel...
it can be activated, but it is only worth about 2 mpg. message me if you want to know more
You can use lean cruise with hp tuners. Just change the platform type to V (holden), copy over your system options from gmt610 to v. Fill in the lean cruise tables. Write entire. Enjoy!
1998 GMC K1500 Z71
* L31 350 Vortec
* AUS 43lb injectors
* Comp 08-410-8 with 1.6 rockers
* P59 swap
* Whipple supercharger
* JBA headers
* AFR 190cc heads
* NV4500 swapped
* Cal-Trac traction bars
* 1" blocks, 265/70r17 BF Goodrich KO2s, 17X8.5 ALPHAEQUIPT COMMAND LT
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