Forum » Webinar Questions » GM LS3HP - HP.Tuners Re-flashing

GM LS3HP - HP.Tuners Re-flashing

Webinar Questions

Ask questions about webinar lessons here. To see the Previous Webinars for a complete list of archives tuning webinars. 


Page 1
Author
1321 Views

This webinar was very stimulating ( and I mean that in an enjoyable way), looking forward to you dissecting more of the OEM ecu logic.

Thanks.

Glad you enjoyed the webinar. Reflashing is a very large animal so there's a lot to cover!

Hey Andre,

i missed the live webinar but just caught up.

I am particularly interested in tuning with the stock ECU and am curious about using wideband o2 sensors for this type of application.

For a home tuner can you simply replace the standard o2 sensors and read the information through the OBD port or do you need to plumb the sensors into the exhaust in a more permanent position? (assuming you are going to be tuning in an ongoing fashion while you learn).

No, you can't replace the stock sensors. The best option is to fit another O2 weld bung in the exhaust for your wideband. In the case of the car we used for the demonstration, I'm actually using the rear O2 ports and I've disabled the DTCs relevant to cat efficiency and rear O2 sensor response. You want to leave the front O2 sensors active as otherwise the PCM can't operate in closed loop mode and viewing the STFT and LTFT gives us a lot of information about the state of the tune for aspects such as MAF/SD scaling.

Greetings Andre i have been not able to locate this webinar on my dashboard as i would like to see it cheers

If you click on the webinars tab at the top and scroll down past the list of upcoming webinars you'll see the archive

https://www.hpacademy.com/previous-webinars/optimising-full-power-fuel-delivery-gm-ls3-e38-pcm-hp-tuners/

hi andre what wideband are you using to connect to the hp tuners dongle? are you doing a course on the hp tuners? ie fuel, ignition, torque management and transmission tuning?

I'm using an Innovate LM2. Currently it is connected via the MPVI interface which is a right pain in the arse. For some reason that nobody can really explain, the interface introduces a 0.38 volt offset to the signal (or thereabouts - Actually it varies slightly across the 0-5 volt range to make life harder), which needs to be accounted for in the transfer function.

The current beta software includes serial support for the Innovate LM2 (among others) so you can connect the wideband directly to your laptop. I'll report how that works out as soon as I've got it tested.

Our course that is due for release any day now is a general reflashing course that covers the topics, principles and techniques that relate to any reflashing task. We are then including a library of worked examples where you can follow the process being applied on a particular vehicle. For the initial release we will be including an example tuning a supercharged Toyota 86/Subaru BRZ on the EcuTek platform, as well as three separate worked examples on the HP Tuners platform with an LS3. These will cover basic tuning, scaling the MAF/VVE tables to suit a new intake, and converting to HP Tuners 1 Bar SD operating system. This isn't a complete guide to HP Tuners but it's going to show you the approach to tuning, which tables to adjust and how to adjust them.

Right now we aren't including transmission tuning but that may come at a later point.

Sounds good Andre, looking forward to it.

Here in Australia, lots of guys are using EFI Live to tune their Holden/HSV cars. Any chance of some info on that platform?

For us newbies, a how to guide for actually setting things up would be great. I have read about plumbing in the wide ands permanently if I am only working on my car but am wondering if there is an option to connect straight to the ecu to log the data or do I need to use a pass through controller lice the LM2?

Hi dgp, we've already considered EFI Live, but right now I can't commit to when that might be available sorry.

Hi Andre,

Few questions with the virtual Ve calculations I'm trying to get my head around and some of the idle airflow with ETC issues

After installing a camshaft with high 30's in duration. For idle quality are we looking at mainly "final idle airflow min vs rpm vs gear" and throttle follower airflow step down for dropping rpm after bleeping the throttle to control that annoying drop and hunt or even stall?

With sd tuning what histograms are we setting up to tune the virtual ve coefficients? Is there some way we can change one and it will automatically change the other coefficients in the calculation? I understand the operating zones and zone boundaries, I understand to a point the reason behind the virtual Ve table meaning instead of the computer constantly looking up a 3D table it only has to calculate the zone it's in at that particular time but how do we tune this? If we alter 1 part of the calculation how do we change the others and how do we know where?

Hoping for a super easy answer

I'll deal with your question in 2 parts - Let's start with the VVE as this is now super easy to deal with in the VCM Suite 3.0 software. I would recommend you hold tight for about 2-3 days though as we should have the next worked example online that covers how to optimise the VVE tables ;)

I set up a histogram with the same axis and break points as the VVE table (In the Edit menu, select Virtual VE Editor - This will display a conventional looking VE table based on the VVE coefficients and we can edit the table here and then the editor will recalculate the new coefficients) and log the parameter EQ Ratio Error (error between commanded lambda and measured lambda). This will tell you how far away from target you are and you can then apply the error to your VVE table and the recalculate the coefficients to correct the VVE table.

Now let's deal with idle control - In all honesty getting good idle control with a large cam takes probably longer in my opinion than the rest of the tuning process. Particularly when you factor in cold start and the transition from park/neutral into a gear. At some point we will do a full tutorial on this but for now here's some quick tips:

I start by addressing the Target Idle Speed table and bump this up to something realistic for the size of cam your'e running - You're going to struggle to get good results if you're still targeting a 550 rpm idle when hot for example. I'd suggest 750-850 depending on cam. Make sure your idle max and min don't fall inside the rpm range your now targeting.

Since the idle airflow is achieved through the ETC position, and you'll need more throttle opening to achieve your target idle, you will likely find that the throttle position hits its maximum value and hence you can't achieve your target. You can address this by increasing the 'Percent Max' parameter under the Idle / Airflow tab. Depending on the size of cam you may need to increase this 1-2% so you can actually achieve your target idle speed.

The main table you'll adjust to affect idle speed and idle quality is the Final Idle Airflow Minimum. I start by adding 15-20% to the values around the idle target speed and interpolate/smooth the table to maintain a smooth shape. You will also need to adjust the Startup Airflow to ensure clean starting and transition to idle and the transition tables to prevent stalling or flaring as the transmission is shifted into/out of gear. You can log the actual airflow at idle to give you a true indication of what is required once the engine is actually idling happily by itself.

This is the 2 minute guid but it should get you ahead of where you are now :)

Thanks for the reply bud, All good! See once you select speed density 2bar OS and the patch it gives you a virtual Ve table to tune as you do a normal ve table, just not the nice % based numbers I'm used to seeing but quite large caluculation numbers into the 2000's

Got the idle sorted and yes I agree it takes forever to get right and the wait for cold start recheck is annoying. Set up the lambda err histogram and worked perfect. Very easy once I had a table