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Convert an existing MAP-based VE table to Throttle Opening

PostPosted: Wed Nov 18, 2020 6:22 am
by parsonsj
I''m considering converting my Radical SR8 (V8 with 8 ITBs) from an M150 GPR MAP-based VE table to an Alpha-N tune. My idle is at about 87 kPa, so I don't have much fidelity, and I'm finding it difficult to get consistent lambda / closed loop injector adjustments. I've tried carving the VE table to smaller horizontal slices for more resolution, but I think I'm chasing a basic lack of fidelity.

I'm wondering if there is an accepted strategy or best practice to convert my existing VE table based on logs or calculations? I also have a throttle-opening-based fuel map (injector pw as a function of throttle opening for Y and RPM for X).

Many thanks!

John

Re: Convert an existing MAP-based VE table to Throttle Openi

PostPosted: Wed Nov 18, 2020 8:32 am
by Stephen Dean
Hi John,

Changing from a MAP based table to a Throttle based will require retuning.

This is a link to the M1 Multi Throttle tuning guide.

Re: Convert an existing MAP-based VE table to Throttle Openi

PostPosted: Wed Nov 18, 2020 10:07 am
by parsonsj
Hi Stephen,

Many thanks!

Alas, my GPR-based firmware is older, and doesn't seem to have the new tables (Engine Efficiency Boost Pressure Compensation and Engine Efficiency Airbox Pressure Compensation).

Its build version is 1.4.0.239, firmware version is 1.01.0006, and system version is 1.04.00.0054

I'll contact RDS (my dealer) and see about a firmware upgrade.

John

Re: Convert an existing MAP-based VE table to Throttle Openi

PostPosted: Wed Nov 18, 2020 12:15 pm
by parsonsj
For fun, I upgraded an older GPRP firmware that I had run a couple of years ago to the latest firmware, and found those tables.

I was unable to set Inlet Manifold Pressure Estimate Mode to "Airbox Pressure Relative". I only had the following choices (and I doubled checked that I had an Airbox Sensor Resource assigned and calibrated):
Ambient Pressure Relative
100 kPa Relative
Boost Pressure Relative

In this case, would locating the Ambient Pressure Sensor into the Airbox work? Or have I done something wrong?

John

Re: Convert an existing MAP-based VE table to Throttle Openi

PostPosted: Wed Nov 18, 2020 2:49 pm
by Stephen Dean
Hi John,

That document has to be updated to match the names to the current channels, so for Airbox Pressure Relative use Ambient Pressure Relative.

Re: Convert an existing MAP-based VE table to Throttle Openi

PostPosted: Thu Nov 19, 2020 12:12 am
by parsonsj
Hi Stephen,

My firmware supplier says that's not a near-term option.

Can something similar be done without these new tables? (Actually just one since I'm NA)

John

Re: Convert an existing MAP-based VE table to Throttle Openi

PostPosted: Thu Nov 19, 2020 8:47 am
by Stephen Dean
Hi John,

What is the name of the firmware that you are running (or send me your ECU serial number and I'll see what licence is in it)? Without knowing the firmware, I can't point you in a direction to resolve this.

Re: Convert an existing MAP-based VE table to Throttle Openi

PostPosted: Thu Nov 19, 2020 9:31 am
by parsonsj
Thanks Stephen.

I think that information is above (firmware versions, etc.)

It's provided by Race Data Systems in the UK, and the reason I'm using it is for the Geartronics sequential shifter control and support.

Should I send a copy to support@motec.com ?

Re: Convert an existing MAP-based VE table to Throttle Openi

PostPosted: Thu Nov 19, 2020 10:28 am
by Stephen Dean
Hi John,

Looking through the Package it is possible to be done, I have sent you the information needed.