1227165 Running 12P for a GM 2.5L Iron Duke with Turbo

American Delco GM ECUs and PCMs, ALDL, OBD 1.5.
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1227165 Running 12P for a GM 2.5L Iron Duke with Turbo

Postby Mark_ZZ3 » Tue Apr 11, 2017 4:46 am

Starting a new thread with my latest project. I've been browsing the site for a while, and now entered into the 12P zone.

Project: 1987 S10 Truck with a 2.5L 4 cyl TBI engine running at 1227165 PCM and $53 code. Pretty basic. No knock sensor. Speed density.

1227165 PCM
TunerproRT for calibrations
Craig Moates APU1 Chip reader/burner (no fancy flash tool ... just swap chips!)

Upgrades: Added Turbo and Intercooler from Volvo S50 (or something like that). Front mount side to side intercooler. Decent sized Turbo for the 2.5L.

Attempted to run Turbo on stock PCM with stock code, tweaking fuel and spark. Worked pretty well, but very limited tuning due to so few values. Was worse when you used a 2 bar MAP. 1 bar MAP worked better!

Enter in 12P!!! (insert dramatic music).

I was very surprized at how easy it was to use the 12 code on the 165 PCM. The wiring for the old S10 was almost perfect. Only the shift light was in the wrong spot. So without having to change ANY wires, I burned my first 12P version, and set to work getting it to run.

- First step was setting spark reference angle. Turns out my engine used 90 degrees. Makes no sense to me how this works, but that is how it is. I tend to ask less questions about the values, and just turn the dials until things work.
- Next was to set the fuel injection base (grams/sec). This took some time. Go up, do down, go way up, go way down. Get it to start. Then try to drive. Stall. Stall. Stall. Finally get the number close. Test drive. And with 30+ more drives, I figured out which way the value had to move to get it to run. Ok got a good base.
- Still ran so so. Go inside.
- Try again ... cold engine ... runs like a top! Cold fueling works. Warm doesn't. So tweak those values. And it starts to drive nice.
- Copy timing tables over form the old $53 version. They ran nice. Work well ... but under boost, it pings. Go to basics and remove timing in boost (BECAUSE I NOW HAVE A TABLE IN BOOST!!!).
- A bit more tweaking of the AE settings, no more dead spot.

So, with some minor work, the 12P code is AWESOME. TBI, stock fuel pump, stock injector ... runs up to 6 PSI boost and isn't leaning out. Nice to drive too.

I figure I am the limits of the stock fuel system. I knew that was going to happen, but having a working setup makes this so much nicer. Next steps are to use a larger TBI unit from a 2.8L that has two injectors. Back to basics again with fuel and see if I can get the boost up to 10 or so.


My issues thus far:

- Flex Table B. I set it up to operate a boost control valve. I have the stock Volvo relay plumbed to all the right ports. My flex table uses 100-150 KPA on the X-axis and 400-6000 RPM on the Y. I set the values to 99.61 for where I wanted the rely to be operated. Under testing it was backwards. I swapped the values to ZERO where I wanted it to be powered, and 99.61 where I don't and it kind of works. In logging, it won't operate until it gets into boost. Which is perfect. But I want it to shut off when it gets over boost ... but it stays active even though the flex table values state otherwise. It seems to get locked until you drop the throttle/RPM. Maybe using RPM is my mistake and I need to use MAP for both X and Y axis instead? Hmm ...


Well this is my project (well it's my son's ... I'm an 80's Camaro with a TPI engine sort of guy ... but his truck used the same `165 PCM.). This has been fun. So much different than other tunes.

Mark.

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Re: 1227165 Running 12P for a GM 2.5L Iron Duke with Turbo

Postby MAGP » Tue Apr 11, 2017 6:14 am

Good to see something slightly different being tuned. Keep us updated with your progress on the S10 but also let us know about your Camaro.

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Re: 1227165 Running 12P for a GM 2.5L Iron Duke with Turbo

Postby Mark_ZZ3 » Tue Apr 11, 2017 7:50 am

MAGP wrote:Good to see something slightly different being tuned. Keep us updated with your progress on the S10 but also let us know about your Camaro.


For sure. The S10 with 2.5L is my first stab at the 12P code. Quite surprized at how well it works. Seems too simple to work like it does. I was days away from re-pinning a 7730 to the '165 and then trying to hack the Turbo SyTy code to make it work. I can only imagine the steep learning curve that will have.

I've worked with the $32 and $6E stuff on the TPI computers. I'll do some wiring checking and see if I can just convert over to the 12P code and give it a shot. It will be a project unto itself. For now having the TBI work with boost, and be driveable it very exciting. It gives some new hope for future mods.

Now ... if the 12P could only control the 8 coil packs on the LS/LQ V8 engines ... :-)

Mark.

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Re: 1227165 Running 12P for a GM 2.5L Iron Duke with Turbo

Postby Mark_ZZ3 » Tue Apr 11, 2017 2:28 pm

Here is a pic of this project:

No fancy tig welding. Cut Exhaust, reweld, fabricate flanges, make downpipe, make inlet tubes, make throttle body hat. My 19 year old Son's handy work.
(Unsure how to directly link google pic here ... so here is link to pic)

Image

Image

Project has been named "RAT10" ... take an S10, apply RAT theme, and general Fun and Fabrication. It's been lowered, upgraded with better suspension. Basic no option truck from factory.

Mark.
Last edited by Mark_ZZ3 on Thu Apr 13, 2017 11:00 am, edited 1 time in total.

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Re: 1227165 Running 12P for a GM 2.5L Iron Duke with Turbo

Postby Dazza92VP » Tue Apr 11, 2017 2:32 pm

It can run 8 individual coils with one of these viewtopic.php?f=11&t=2913 need to confirm with vl400 to make sure it is ok with the 24x pickup but I think he said it can

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Re: 1227165 Running 12P for a GM 2.5L Iron Duke with Turbo

Postby antus » Tue Apr 11, 2017 4:13 pm

Just for the record you should be calculating your injector rate with the injrate calculator tool based on your injector specs. This should get you closer to correct straight up, and likely you'll find that your warm running is then correct, and its cold start that isnt. You can then tune your cold start enrichments to suit. Did you confirm your timing by putting it in diag mode and checking your physical timing was showing 10 degrees? Having said that im glad you a got a good result!

As for your relay, how do you have that wired? Is it a 12v relay?
Have you read the FAQ? For lots of information and links to significant threads see here: viewtopic.php?f=7&t=1396

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Re: 1227165 Running 12P for a GM 2.5L Iron Duke with Turbo

Postby Mark_ZZ3 » Wed Apr 12, 2017 1:24 am

antus wrote:Just for the record you should be calculating your injector rate with the injrate calculator tool based on your injector specs. This should get you closer to correct straight up, and likely you'll find that your warm running is then correct, and its cold start that isnt. You can then tune your cold start enrichments to suit. Did you confirm your timing by putting it in diag mode and checking your physical timing was showing 10 degrees? Having said that im glad you a got a good result!

As for your relay, how do you have that wired? Is it a 12v relay?


I did try the injrate tool. As I am working with an odd engine, finding flow specs on the single injector has been a challenge. So I best guessed it and got a starting point. I moved the grams/sec value by 0.0020 increments and that seemed to provide the seat of the pants feel. Then watched the narrow band O2. This was good enough to get it running. Plans are for a wideband ... since 12P supports that! Forgive my backyard mechanic style ... I try to combine math, science and experience. And sometimes, luck!

I will reverse engineer my inj value and see what it says the flow rate is.

I had not tried the Diag mode to verify timing. I will have to research that and see how to do it. With the TPI's there is a set timing connection, but I had not seen it with this engine. Rather the distributor almost looks keyed to fit in one position only.

Under boost we had been hearing the pinging, and I simply took out timing in that RPM/Boost range little by little to where we did not hear the pinging, and it felt like it was running properly. Again, sometimes I pay less attention to the actual value, and more to how the engine responds. It's a bit of blind faith at times. The more experience with 12P I get, I'll become more by the book - so to speak.

Also consider ... once you get the engine to fire and run, the excitement of driving takes over, and then you tune on the fly. Which usually means you have no idea what you tweaked to make it work. lol.


The relay is a stock Volvo part for the wastegate. So yes 12V. I have it working where it will energize at above 100Kpa and in the RPM range I want. But it doesn't un-energize when it gets to the Kpa value I want. It only drops off when the RPM drops. So I re-did the table using only Kpa on both X and Y axis thus making the value along the diagonal. I'll see if this works. The numbers still seem backwards as ZERO energizes the relay, and 99.61 (255) does not. The log file does show the off (zero) and on (99.61) working as expected, but the values in the table seem backwards to me. I guess as long as it operates when I need it to ...

I should also say ... the flex table B which I am using ... odd thing. With the engine not running, if I move the throttle, at 40%, the relay will pulse/flutter. There is no Kpa or RPM at this point, so I don't know why Flex Table B would come in to play here. I recall reading somewhere you can set a flag where the flex table only comes into play when the engine is running ... but I have not found that.


12P has been a very exciting upgrade. Brought new life to the project.

Mark.

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Re: 1227165 Running 12P for a GM 2.5L Iron Duke with Turbo

Postby VL400 » Wed Apr 12, 2017 4:33 am

Dazza92VP wrote:It can run 8 individual coils with one of these https://pcmhacking.net/forums/viewtopic.php?f=11&t=2913 need to confirm with vl400 to make sure it is ok with the 24x pickup but I think he said it can

Yep, works on the 24+1 trigger type.


Mark_ZZ3 wrote:The relay is a stock Volvo part for the wastegate. So yes 12V. I have it working where it will energize at above 100Kpa and in the RPM range I want. But it doesn't un-energize when it gets to the Kpa value I want. It only drops off when the RPM drops. So I re-did the table using only Kpa on both X and Y axis thus making the value along the diagonal. I'll see if this works. The numbers still seem backwards as ZERO energizes the relay, and 99.61 (255) does not. The log file does show the off (zero) and on (99.61) working as expected, but the values in the table seem backwards to me. I guess as long as it operates when I need it to ...

I should also say ... the flex table B which I am using ... odd thing. With the engine not running, if I move the throttle, at 40%, the relay will pulse/flutter. There is no Kpa or RPM at this point, so I don't know why Flex Table B would come in to play here. I recall reading somewhere you can set a flag where the flex table only comes into play when the engine is running ... but I have not found that.


Excellent work on the conversion :thumbup:

There are flags in the flashtool where you setup the axis config. One is called "Invert Output Duty Cycle" so you can have 0 off and 100 fully on. And another is called "Active only with Engine Run".

For the TPS thing may need to check the config is correct. By default its using TPS and RPM. Maybe the cal/bin wasnt saved before exiting the flashtool editor?

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Re: 1227165 Running 12P for a GM 2.5L Iron Duke with Turbo

Postby Mark_ZZ3 » Wed Apr 12, 2017 6:48 am

Hmm. I didn't use the flashtool to start with. I started with another 4 cyl config that was in the forum. I figured the fueling would be closer than the V8. I assumed I could just adjust the Flex Tables in the XDF file. IT seemed simple and it seemed to work. Pick X and Y axis, and the value. Good to go. Somewhere the Invert output duty cycle is done, but that option is not in the XDF (at least where I can easily see).

I did add my own Boost data point which I like over the Kpa. Easier to see on the graph for the wastegate control.

I will have to try out the flash tool and see how that works.

I'll drinking from the firehose as they say.

Mark.

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Re: 1227165 Running 12P for a GM 2.5L Iron Duke with Turbo

Postby MAGP » Wed Apr 12, 2017 6:52 am

Mark_ZZ3 wrote:Under boost we had been hearing the pinging, and I simply took out timing in that RPM/Boost range little by little to where we did not hear the pinging, and it felt like it was running properly. Again, sometimes I pay less attention to the actual value, and more to how the engine responds. It's a bit of blind faith at times. The more experience with 12P I get, I'll become more by the book - so to speak.
Be careful adjusting timing by hearing and/or feel. An engine can have knock that you wont hear and that is one reason the old wives remedy of advancing until you hear knock and then take out 2 degrees come about. Problem is knock can still be present even at that timing.

Professional tuners use knock detection equipment when tuning, even on the street. Take a look at this http://www.d-series.org/forums/diy-foru ... t-can.html and considering making it to help with your timing adjustments.

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