Doing a run of 90-93 NICO ECUs

[CrazyTrance]

Would love to get one possibly later this year... maybe not till next year... how long will you be offering to do this?

- Chase

[z1 zonly]

as opposed to 4 way?

Mehhhh-be

I'm not ready to order at this very moment, but I would like to know for reference.

I can think of at least 3 different tunes I'd like to have. 4 is max.

[rogue240sx]

is there anyway to have 2nd gear starting selectable incase i need it?

[450Z]

Wes, You had mentioned that there are some options available when you reflash the EPROM. Other then the obvious fuel and ign maps that you change, are there any other parameters that you could change that could be advantages to me? I assume that the fact that there are no auto trans signals coming into the ECU it doesn’t affect any of the engine maps? I'm also not running any AC, PS, EGR and have removed the traction control throttle plate and motor.I hope to have the ECM shipped to you today.

[SSDwellah]

hey Wes, I have a question for you. Years ago I wrote a small Rom tuner app that takes those .adr files and rom dumps and allows you to modify the tuning (kind of the like the original japanese one that was released except mine was going to be open source and in english).

Well I was recently motivated to look into this again, and I have also had a little bit of success disassembling the code - since most mid 80s to 90s Nissans seem to use Motorola 6802 or 6803 clones.

Anyway, I got a got a hold of an early 60U00 rom file and this it seems like the speed limiter is set for 236 kmh (~147 MPH) and the rev limiter is set for 6700 RPM (this one seems just a tad low). Have you see other safe values for these on stock nissan ECUs? e.g rev limiter at 7000 (which mine seems to be closer to, according to the tach)... or speed limiter at 155 MPH, which is not far from 147MPH, and 300ZX TTs are rumored to be governed there too (IDK never took my swap up that high and the speedo sensor to ECU is probably screwed up since I am using Z32 MT).

[Carl H]

nissan tachometers are off by a fair bit...i see this alot when recalibrating tachs for rb swaps.my own car reads 8k on the tach but datascan sees it as 7600; a good 300rpm difference.what happens is that even tho ecu will revcut the engine is still spinning so it wont stop exactly at the revcut...so when seting revlimit you should set it a hair lower than actual desired.as far as the speec cut goes, same deal...nissan speedos are a hair bit inflated from factory so while it might read xx mph, it is really only going yy mph; remember that tire and wheel sizes as well as final drive differences will skew the speedo output.when i swapped a r33 auto rear end into my car (4.36final vs std 4.08) i had to order a 21 tooth pinion for the speedo to get a correct readout.

[SSDwellah]

nissan tachometers are off by a fair bit...i see this alot when recalibrating tachs for rb swaps.my own car reads 8k on the tach but datascan sees it as 7600; a good 300rpm difference.what happens is that even tho ecu will revcut the engine is still spinning so it wont stop exactly at the revcut...so when seting revlimit you should set it a hair lower than actual desired.as far as the speec cut goes, same deal...nissan speedos are a hair bit inflated from factory so while it might read xx mph, it is really only going yy mph; remember that tire and wheel sizes as well as final drive differences will skew the speedo output.when i swapped a r33 auto rear end into my car (4.36final vs std 4.08) i had to order a 21 tooth pinion for the speedo to get a correct readout.

Oh yeah I definitely know about nissan guages ... shall we say optimism? But since my car is a Z32 with a stock Z32 gearbox and speedo sensor and wheels then from the speedo guages perspective it's at least consistent... it's the ECU's perspective I am worried about.

[z1 zonly]

Wes, how much for a 4-way switchable ECU? 1) Conservative high power 2) Critical mass high power 3) MPG-friendly 4) Valet?

What about the differences in TCS or Active ECU's? Does it matter at all?

[Carl H]

werd.not sure what you mean tho about the ecu's perspective...the speedsensor isnt a major load sensor, its there for speed cut and for decel (iac duty cycle modification).sorry, can you be clearer?

Oh yeah I definitely know about nissan guages ... shall we say optimism? But since my car is a Z32 with a stock Z32 gearbox and speedo sensor and wheels then from the speedo guages perspective it's at least consistent... it's the ECU's perspective I am worried about.

[SSDwellah]

werd.not sure what you mean tho about the ecu's perspective...the speedsensor isnt a major load sensor, its there for speed cut and for decel (iac duty cycle modification).sorry, can you be clearer?

Sure let me elaborate...

The speedometer gauge was factory calibrated for the following: X = 300ZX wheels/tires, Y = 300ZX N/A Rear End Ratio, and Z = 300ZX Speedo Signal

In my setup, X, Y, Z have not changed at all: the car is a 300ZX Z32 NA using an Z32 N/A M/T, speedo sensor, and stock VLSD, with stock wheels/tires. So the gauge is accurate for this setup.

However the ECU is expecting a different X, Y, Z for the Q45: maybe the overall tire diameter is close but I'm not sure... I know the diff ratio should be way different. So in theory, the ECU will think I am going faster or slower than my real speed and will speed govern at the wrong limit.

As a contradiction/counterpoint: Now there is another interesting tidbit: On every nissan speedometer I have taken out before (B13 sentra, S13 240SX, Z32 300ZX) I see a marking that says "1024 RPM = 60MPH" or something similar. If this is true and consistent, then it seems that Nissan sets their speedo sensors up such that what comes out of them is a signal with 1024/60 HZ per 60MPH, in which case both any contemporary nissan gauge and ECU will be reading the right speed (so long as the speedo sensor itself is calibrated for the tires and diff ratio consistent with the 60MPH=1024 RPM rule). I can't confirm this, but it seems logical. I think that is why they used to sell different gearsets for their speedo sensors (they may have been color coded too) to compensate for swaps in differentials, rather than just recalibrating the speedo itself.

[elwesso]

just letting everyone know that i am waiting on 1 other ECU and I'd really like to get everyone that wants in to hit me up now, or as soon as possible, it really makes it easier for me.

[Carl H]

I think i would be inclined to belive that you are on the right track as using the s14 speed sensor in my rb20's trans results in the ecu seeing the correct speed...after all the speed sensor is just an ac motor from which the ecu derives the speed.either way, the car should function the same as the speed sensor is not a key load sensor but part of a secondary subsystem, this is why you can not wire it in and the car will still function correctly.

Sure let me elaborate...

The speedometer gauge was factory calibrated for the following: X = 300ZX wheels/tires, Y = 300ZX N/A Rear End Ratio, and Z = 300ZX Speedo Signal

In my setup, X, Y, Z have not changed at all: the car is a 300ZX Z32 NA using an Z32 N/A M/T, speedo sensor, and stock VLSD, with stock wheels/tires. So the gauge is accurate for this setup.

However the ECU is expecting a different X, Y, Z for the Q45: maybe the overall tire diameter is close but I'm not sure... I know the diff ratio should be way different. So in theory, the ECU will think I am going faster or slower than my real speed and will speed govern at the wrong limit.

As a contradiction/counterpoint: Now there is another interesting tidbit: On every nissan speedometer I have taken out before (B13 sentra, S13 240SX, Z32 300ZX) I see a marking that says "1024 RPM = 60MPH" or something similar. If this is true and consistent, then it seems that Nissan sets their speedo sensors up such that what comes out of them is a signal with 1024/60 HZ per 60MPH, in which case both any contemporary nissan gauge and ECU will be reading the right speed (so long as the speedo sensor itself is calibrated for the tires and diff ratio consistent with the 60MPH=1024 RPM rule). I can't confirm this, but it seems logical. I think that is why they used to sell different gearsets for their speedo sensors (they may have been color coded too) to compensate for swaps in differentials, rather than just recalibrating the speedo itself.

[z1 zonly]

just letting everyone know that i am waiting on 1 other ECU and I'd really like to get everyone that wants in to hit me up now, or as soon as possible, it really makes it easier for me.

Perhaps I would if I could get my question answered. No response through email, nor on the forums. Here it is, one more time, plain and simple:

4 way switching on a '91 non-TCS, non-active ECU--how much?

Tunes, if necessary:1) Conservative high power2) Less conservative high power3) Detune for better MPG4) Valet.

[elwesso]

Sorry I thought I responded to your reply earlier, not to blow you off or anything.. My apologies.

I am not doing 4 ways right now... I am focusing on primarily 2 ways due to the amount of hardware I have to buy.

[thejapino]

Hey wes, If you need cores, I have 3. Or anybody else that needs an ECU! All of them are 90-93. I'll get them to you cheap.

My link: zer...d=172

[maxnix]

3) Detune for better MPG

As I understand it, it is not the tune but the application of the right foot that determines MPG, besides idling time, fuel quality, etc.

[qsiguy]

That certainly is the most important and effective means of improving fuel economy.

There is, however, many areas in the ECU that could be tweaked to force the car to run leaner at cruise. The O2 sensor rich/lean set points can be adjusted, the maps in the cruise areas can be leaned. Even all these adjustments will only yield a limited amount of gain. Furthermore, the Q isn't the vehicle I would use as a test bed for these modifications. While the Q will happily run leaner than 14.7 AFR at low loads, like any other engine, IMO this isn't the platform for it.

I work on mileage improvement experiments all the time on my Toyota p/u and I'm not worried about any potential damage that may be caused. In fact, I'd like to get rid of the Toyota and get a Nissan p/u or Sentra in the 90-94 year models so I can mod the ECU and tune for mileage. I'd personally rather start with a economical vehicle and shoot for really high MPG numbers.