Nissan ECU Tuning

zef · Joined: 17 Mar 2008 Posts: 7

I have set the revlimiter to 7800 rpm (high octane) and 7400 rpm (low octane) but it doesnt seem like the revlimiter is working, can rev past 8000 without any sign of the limiter. Anyone who has any suggestions what the problem can be?

Seccond thing I was thinking of is the TTP max and TTP min.
Original is:
72 72 72 72 80 80 88 88 179 179 179 179 179 154 154 154
I have read somewhere on this forum that the first eight should be TTP max ( 72 72 72 72 80 80 88 88 ) and the following eight should be TTP min ( 179 179 179 179 179 154 154 154 ).

I have changed injectors for 444cc skyline injectors, but how do I adjust TTP min correctly for this? My first guess was to multiply all values by 370/444. But now Im not sure anymore, I have seen tunes from other people that sets the TTP max to something like:
72 72 255 255 255 255 255 255 255 255 255 255 255 255 255 255
This makes me think there is no TTP min only TTP max

Is the 16 values table both TTP max and TTP min?
How do I adjust TTP min (if it exist) to fit my new injectors (444cc)?

cb_drift · Joined: 04 May 2004 Posts: 472 Location: New Zealand

leave ttp max and ttp min alone and drop the K value to get fueling correct and adjust the null to get the idle afr's (very basicly)

the tunes with mostly 255's in them are probably a result of someone playing with liveedit (it did that when injector sizes changed)

you can get a ca18 ecu to idle perfectly and run perfectly with no need to change ttp min/max at all...

probably also find that the fuel maps in the roms that had the ttp min/max set to mostly 255 had lots of negative values on the fuel map to get their idle sane again at a guess

zef · Joined: 17 Mar 2008 Posts: 7

Oh, ok.

Could you please just have a quick look at my parameters to see that I´m not totaly off. Engine is CA18DET in S13 with MEC-D007 ECU. Mods are dual exhaust cams, T28 turbo, FMIC.

I have no clue on what code the tune is running (got a stage 2 chip with the car) but fuelmap looks like JDM with minor changes at full load. The chip was running great before I started to change it (except that it does not have any revlimiter).

What I have tried to do is to adjust it for Skyline injectors (444cc) and Z32 maf.

Just to not confuse anyone with the k value is 405. I don't know why it is separated in two fields in this editor 1 149 is 256 + 149.

Fuel and Ignition TP Scale is adjusted by a factor of ~0.84

Havent had a try with original TTP max/min (changed back in the picture). I have tried with:
72 72 72 72 80 80 88 88 150 150 150 150 150 130 130 130
the engine idled ok but low but past ~3000rpm it ran like crap.
Could this have anything to do with my modifications on the tune or is it maybe something hardware related like a boost leak?