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M84 nearly maxing out

PostPosted: Thu Aug 31, 2023 6:02 am
by luchj
Hello everybody,
the M84 on my R33 GTR is nearly on the edge of its capabilities.
All the outputs are used and inputs too.
I need to add coolant pump control and PWM control for a DHB or a SSR for my twin 044 pump system. Maybe I will need a flex fuel sensor too in the upcoming future to run E85 mixed with pump 100 and lord knows what else.
I actually have a map with 4 boost steps running pump gas + toluene 5%, I would also like to have a switch to let me choose between 2 maps (at least 2 different ignition advance tables) to let me drive both pump gas or toluene mix.
I know that M84 doesn't have multi config as the M800 but maybe there's a trickery to do that.
That said my doubts are between buying an expander (expensive expander :o ) for the M84 or upgrading the ECU to another model.

Luca

Re: M84 nearly maxing out

PostPosted: Tue Apr 02, 2024 11:17 pm
by sardengineering
Good day

For the benefit of anyone else reading this, the M84 can't be used with the E888 nor the E816. The only expansion module you're able to use with the M84 is the Ignition Expander Module. Based on the scenario being described, an appropriate upgraded ecu should be chosen to replace the M84.

Re: M84 nearly maxing out

PostPosted: Wed Apr 03, 2024 9:46 am
by Stephen Dean
As Damien said, the M84 does not have the ability to work with the E8xx expanders.

From your description, and planned upgrades, you would be better off selling the M84 (they make good money second hand that I have seen) and moving to an M150. You could go to an M130, but I think that you will max out the IO on that quickly as well, with the M150, you will have more IO available.