first pull and limitations

[Juancitosport]

Hello everyone. My name is Juan, im new at hp platform. I have a 2011 a4 quattro s tronic (eurospec DL501) with built engine and gtx3071r gen2 custom turbo kit. My tuner couldn't tune my car with eurodyne (thats was my plan A) bc of my euro spec set up, so i bought the HP platform.

So, while im trying to get a refound for my tuner to pay an HP tune (things that happens when you live in a LATAM country with dollars restrictions), i started messing around with the car on wg cracking pressure boost (around 14psi, boost controlled by GFB force III EBC) and OEM fueling (my set up is intended to use Mabotech DI injectors, autotech HPFP and walbro 450 LPFP).
My whole experience is with stand alone tuning so this is like starting over for me lol. I?ve been reading a lot of torque based tuning for MED17 but every forum a read is in VAG lenguage. So im learning torque base tuning AND how to traslate VAG to HP at the same time.

I downloaded some tunes from this forum to check them out just to have a hint about what to do and they were extremely helpful, thank you for sharing! the car improved pretty much from the stock tune but now i think im hitting a limitation i cant find, so maybe someone can help me move on a little bit more and learn a little bit more aboute tuning this ECU.
I attached the first log i made when things started to go a little crazy, it seems like the car is limiting torque to 350/360NM clutch or load to 200, dont know which one (my guess is load to 200), bc when i hit 200 in load the timing goes back (no timing pull, i think some table is limiting the output) and load starts to oscilate. This situation started showing when i tried to increase boost a little bit from 14psi.

FYI, the Optimium torque table is escalated to 250 in the load axis, the max load is also at 250, and the torque to load table is matched with the optimum torque one, so dont know where to look for the limitation. The torque monitoring tables also are increased and matched with the tables i mentioned before. Any help will be appreciated

About the lambda strategy, i used what Tyler explained in a post about taking the control temperature down so the system will follow the temperature control lambda tables, and im staing pretty rich just to play safe for now, until i can push boost a little bit up

[Juancitosport]

ive just made two pulls, one with ebc tuned off (14psi) pull2 and one with ebc at 50%DC pull3, and boost remains the same, with the difference that in the pull with DC the oscilations are noticiable. So im thinking the car is limiting the boost to aroun 14.5psi, and the oscilations are bc the DV opening, maybe?

[TylerJDubbs]

rev7 pull2 actually looks pretty damn good for low boost, what's your file look like if you don't mind posting it up here I can give you some pointers

[Juancitosport]

Of course. I started tuning my stock file based on a couple of files you upload for stage 2 and went from there. I copied the lambda strategy and the VVT for smother idle you explained in some other post. i've also been reading about the homogeneous inj strategy you have been talking about but didnt understand much about that.
I took a lot of time to make a very realistic compressor, efficiency and turbine map for GTX30 (once i figured out the actual units in the HP tuners software are wrong lol) and then figure that i dont need those maps if im using EBC, but at least i think they are accurate, maybe for someone else it would help

[Juancitosport]

I think i could lower the max load requested in lower RPMs bc the turbo wont give me much load below 3500, so the requested and actual load would be more accurate, but will that affect performance in any way?

Also, the transmission is tuned with TVS stage 2 tune, maybe is relevant in some torque management way i dont know yet lol

[TylerJDubbs]

I think i could lower the max load requested in lower RPMs bc the turbo wont give me much load below 3500, so the requested and actual load would be more accurate, but will that affect performance in any way?

For a start, raise HPFP request to 158bar in the request maps ([ECM] 15299 - DI Desired Fuel Rail Pressure (Homogeneous)) and the other variants, also switch to disabled here [ECM] 15390 - DI Desired Fuel Rail Pressure Rate Limiting

Better tune your load max to represent the the 4K spool point you have, your most post #5 shows you get it

Then you can also lean out the lambda to around .88 in power enrichment and .836 in temp control as you wont have the fuel volume to go very far with your size of turbo. do this by zeroing out the full operating temp points in [ECM] 29213 - Base Cold Correction Adder then retuning temp control and PE targets

watch your DI advance to see when you max out injection time and then youre pretty much all set

[Juancitosport]

I will do everything you point and make a couple of logs, but i would like to understand some concepts about whay im doing. The limiting factor that was holding me back on boost was the DI fuel rail pressure? I like to see what is happening here lol, bc no matter what DC i request on EBC, boost wont go up. I know that the OEM fuel sistem max out at 20psi with this turbo, bc i built several GTX30 projects with unitronic software stock fueling and requests that boost (about 400whp in fwd apps). I think i had some concept wrong bc i was looking at inj pw to see when im reaching the limit

[TylerJDubbs]

I will do everything you point and make a couple of logs, but i would like to understand some concepts about whay im doing. The limiting factor that was holding me back on boost was the DI fuel rail pressure? I like to see what is happening here lol, bc no matter what DC i request on EBC, boost wont go up. I know that the OEM fuel sistem max out at 20psi with this turbo, bc i built several GTX30 projects with unitronic software stock fueling and requests that boost (about 400whp in fwd apps). I think i had some concept wrong bc i was looking at inj pw to see when im reaching the limit

Right now I can see nothing holding you back, I just know you?re going to need more HPFP for fuel volume to make power.

boost controller must not be hooked up or working correctly because you didn?t hit any limiter as far as I can see.

The boost you will actually be able to achieve is safe to run at .836 max enrichment

DI advance and MS injection time are identical because the param is actually Effective injection duration in degrees it just gives you a better idea how close to limits you are than the MS does

[Juancitosport]

The Force 3 install is pretty straight fw, i dont think i messed up there (I will take a second look tomorrow) . If you take a look at log pull3, where im asking boost with 50% duty you will see that the MAF reading starts to increase and then it stops, and boost drops and timing retards, thats why i thought i was hitting some limiter, but maybe it has something to do with the controller.

About the fuel rail pressure settings, i see that the RPM axis goes up to 5000 rpm. Shoul i leave that as it is? what happens after i go up those 5k?

[TylerJDubbs]

The Force 3 install is pretty straight fw, i dont think i messed up there (I will take a second look tomorrow) . If you take a look at log pull3, where im asking boost with 50% duty you will see that the MAF reading starts to increase and then it stops, and boost drops and timing retards, thats why i thought i was hitting some limiter, but maybe it has something to do with the controller.

About the fuel rail pressure settings, i see that the RPM axis goes up to 5000 rpm. Shoul i leave that as it is? what happens after i go up those 5k?

The ECU will target the last cell it sees, so if you have 158bar at 5K it will target that for anything 5K and above so even 7500rpm will still target 158bar

[Juancitosport]

i coudnt resist and went to the car now, double checked the booster install, everything is connected properly, so i dont think im gonna be able to make more boost. Need to figure out why log3 behaves like that when i request boost

[Juancitosport]

i've made the changes to the tune in a new rev, the fueling now is a little leaner, and the requested and actual load started to behave better, need to improve this anyway. But the car wont let me build boost. The harder i push the DC in the booster, the harder the car oscilates and try to hold back power, as you can see in the logs. Car runs flawless with WG boost, and very unstable when i try to build boost. Is there any way i can log if the DV is opening?

[TylerJDubbs]

New logs look great, whatever is causing your issue is not on the ECU side, I would look at how the boost controller is setup and verify you are not hitting any safties like overboost or lean safety’s because it looks to me like the controller is turning on and off, nothing on the ECU side is changing

[Juancitosport]

You are absolutely right Tyler. I forgot to check the EBC safety features. I?m sure that?s the problem. Will take a look and let you know

[Juancitosport]

The over boost was set to 14psi. I?m dying

[TylerJDubbs]

The over boost was set to 14psi. I?m dying

Happens to the best of us ��

[TylerJDubbs]

i've made the changes to the tune in a new rev, the fueling now is a little leaner, and the requested and actual load started to behave better, need to improve this anyway. But the car wont let me build boost. The harder i push the DC in the booster, the harder the car oscilates and try to hold back power, as you can see in the logs. Car runs flawless with WG boost, and very unstable when i try to build boost. Is there any way i can log if the DV is opening?

Now that Im home and have had a look at your file, you need to raise this.....[ECM] 15209 - High Pressure Fuel Maximum Desired Pressure
you also need to retune [ECM] 34911 - TIP Base Pressure to better represent your new turbos wastegate pressure

[Juancitosport]

Here are some logs for pulls in third and 4th gear. Car now pulls strong! i think i need to raise the HPFP a little bit more as you state and retune a little bit of the load tables to match what the car is doing. But super happy!

[Juancitosport]

Im interested in why the clutch torque is almost the same as when i was pulling 14psi but the car is waaaay faster

[TylerJDubbs]

Im interested in why the clutch torque is almost the same as when i was pulling 14psi but the car is waaaay faster

yea you need to bump up HPFP for sure with [ECM] 15209 - High Pressure Fuel Maximum Desired Pressure, and also look at tweaking the .4+ KG/min low pressure pump duty with [ECM] 15493 - Low Pressure Fuel Pump Base Duty Cycle i normally end up just over 80% there to stabilize the high side