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Hi everyone, my first post on this forum :stupid: and my first skyline ever!

I just bought an imported HR31 2 door with the R33 motor and gearbox. This car was built for drift and raced in Japan. Now I have it. :laughing-smiley-014: There are so many mods on the car im still trying to get my head around all of it.

The thing that has me a bit stumped is the ECU. It has been modified in Japan to take 3 eeprom chips (3 programs) instead of one. There is a switch to select program 1 thru to 3 and it also has adjustable knobs on another cotrol unit that is wired into the ECU harness. Im not sure how it all works.

Here is the inside of the ECU

Here is a pic of the program selector

Here is the other control unit with the knobs

The control unit with the knobs is wired in like this

And the plug that the controller is wired into is here

My gesses is that the three chips contain 3 different ignition timing curves and the control unit with the knobs is for changing the air/fuel mixture. But this is only a guess.

Does anyone know how all this works?? Has anyone seen anything like this before?

Edited by marci
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https://www.sau.com.au/forums/topic/170172-what-can-my-modified-ecu-do/
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yer it definetly goes hard so i think i wont be rewiring anything for sure. Just curious to find out how much more I can get. I gess thats why I love cars. its that chase of just a lil bit more...nver enough power :P

but, yep will be taking down the dyno one of these days and figure out the controlls + tune for aus weather and crap fuel.

thanks for the feedback guys :P

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