HP tuners E38/E67 PCM speed Density tuning

Dear members,

I have been tuning cars since early 2000's, started out with your basic Evo/Subaru days and slowly worked my self into many other platforms.

I currently have an issue with E38 pcm that need to be Speed Density for swap and ITB projects.

the only issues i have it at full throttle the car just drops lean, (o2 sensor confirms) fuel pressure there)

using the latest software of HP tuners and untilizing the VVEL virtual VE to pin down all fuel corrections.

keeping stock OS or changing it doesnt help.

i hope i am speaking HPT lingo for those who can help.

speaking NA car now, boosted cars i have worked on and adjusted the boudaries for boost

What happens if you just add more fuel to that area of the VE table.

What is your PE Equivalence ratio?

Injector Duty cycle?

Is it at any part of the rpm range or just anytime you go full throttle? If it all of a sudden drops when going full throttle I would assume an issues with your PE Equivalence ratio. Also what are you doing for a map sensor if you're running ITB? Is it still using the E-Throttle control adapted to ITB?

stock there already there, there is a system from Harrop.

all criteria for PE is correct and i see commanded in log.

VE is tuned and aim a bit rich for safety

what i am just not seeing as to why this is happening. maf is failed properly as well

attached file HPT

Is it at any RPM?

What happens if you just add more fuel to WOT?

Can you send a datalog?

When you change the OS are you just copying your virtual VE map to your main IMRC Open, closed and Dod map?

i didnt change OS, working on VVE still. i would use bluecat to get a base VE table and work from there.

car/start/run perfect, just at wot it would lean out for no reason.

fuel pressure is there as well.

I've just had a look at your calibration and on an initial look I can't see any obvious issue. One thing I'd say is that you don't need to use the blue cat tool with VCM Suite V3.XX. If you go to the Edit menu and select 'Virtual VE Editor' you can make all the required changes inside the VCM Editor now.

Have you got some logs of the issue? What happens when you make a change to the PE or VVE table at the point where it is currently going lean? What is the commanded AFR during a ramp run? Is this matching your PE table values? What happens to the injector pulse width when the AFR goes lean?

hello Andrea,

yes i am aware of this, we can use VVE under Edit but stock cal was just weird.

log attached

change extension to HPL to view from CSV

I've been involved with one itb project using HP Tuners so far and I'm afraid it didn't work out too well as a MAFless tune. The problem is that there is no way of running a true alpha-n load input in HP Tuners and the PCM will always be using MAP for calculations. With itb's the MAP signal isn't a great representation of engine load. For example in your log file you will see that your MAP signal is approximately 90 kPa at about 48% TPS and 96 kPa at 100%. This means that you have almost no resolution across half of the throttle opening. It makes it impossible to achieve accurate mixture control throughout the throttle range. I questioned Harrop about this a few years back when I was involved in the itb project and they had no answers - I'll assume that most of the customers who are using the Harrop itb kit on a stock PCM put up with the inevitable downsides.

You may find that your results are much better if you actually use the MAF sensor for your calibration. Is there any reason you've chosen to remove the MAF sensor?

Anyway on to your actual problem - Do you have a wideband connected to your MPVI interface? What are you using to monitor AFR? What I can see from your log file is that the commanded AFR responds as expected. I can also see that the injector pulse width and injector duty cycle follow the sort of trend I'd expect to see as the rpm increases at WOT.

Hey Andrea,

well with how the setup is going there is no way to make the MAF work because of how its setup.

regarding engine load its probably because MAF PIDS still selected and can scew that.

if i want maf, i would need to custom make a intake similar to say a corvette intake that splits