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Yes I have, I think I mentioned that to you in a PM. IMHO, you should work on getting those intake temps down - either by CAI and phenolic spacers or with meth injection.




Hey Dave,


There are actually 3 modes of ECU communication - built in from the factory and selectable in the rom.

1. bi-directional full duplex - send it a memory address and it responds with a value

2. 14 byte one-way stream read from a list of (modifiable) memory addresses in the ROM.

3. 66 byte one-way stream read from a list of (modifiable) memory addresses in the ROM.


The full duplex mode is what I'd like to use because it is the most flexible, but unfortunately it is very difficult to program into tunerpro. Each value would require at least a dozen steps to program in each PID in tunerpro with no copy/paste option! I am working with a member on the Legend forum (Quaraxkad) that is working on a custom stand alone program for 2way communications.


The 14byte stream is what I'm using in the demonstration. It is the fastest way to monitor multiple PIDs, since the ECU is not tied up with processing the requests of full duplex serial. In reality, the stream is in effect bi-directional because I can modify the addresses it streams in real time with my ostrich emulator. The 66byte stream is what the ECU uses from the factory and contains all of the critical sensor values. It is the slowest because of the length of the stream - each value is only updated about once per second. I re-wrote the streaming program last night and can now select the length of the stream. The problem was that I didn't realize the streaming routine was called 3 separate times per program cycle. It was fixed by pointing all 3 calls to the same routine and defining the stream length variable in tunerpro.


Actually on the Legend there are 2 ignition maps - one for when EGR is operating and another for everything else. The NSX adds one additional ignition map for VTEC. The NSX has 2 additional fuel maps - one for VTEC closed loop and one for VTEC open loop. You would need 3 status PIDs to tune the fuel maps properly on the NSX - Fuel Map Status (open/closed), VTEC status and EGR Status.


The open/closed loop transition is based on a few factors - coolant temp, throttle position and engine load. I'd say its primarily based on throttle position. I can make changes to variables in the program that selects the map to lock the ECU into a certain map for tuning purposes.


There is no VIS modifier at all.


No direct solution for boost yet, but getting the injectors installed and working has led me to understand the whole fueling process within the ECU. I really need to get on my game this year and get a snail hanging off my exhaust pipe :).


-Matt


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