62, 63, E5, E6 ECU investigative journalism

[Matej]

Please accept my apologies, as I know this topic has been beaten to death.
I am aware that all of these are supposedly interchangeable on a '91-96 S13 SR20DET, however, I would really like to know what the differences are, no matter how unimportant.

First, to clarify:
62 ECU - redtop 5-speed
63 ECU - redtop automatic
E5 ECU - '94-96 blacktop 5-speed
E6 ECU - '94-96 blacktop automatic

50F00 MAF - shared by all of the above motors as far as I know, please correct me if there are others

As far as the redtop and early blacktop ECU compatibility goes, the main difference is that the 62 and 63 require a skinny O2 sensor, while the E5 and E6 use the fat one.

When the auto ECU's are used on a 5-speed car, they cause the rpm's to 'hang' and drop gradually when throttle is let off. Some people actually prefer this effect for shifting, some do not. Many are indifferent.


1. Does the fat O2 sensor have any advantage over the skinny one, or vice versa? Are there any differences at all, other than physical?

2. Is it true that the auto ECU's do not have a speed limiter? If true, does that mean they are also missing a rev limiter, or do they still have that?

3. When searching, I read a post where someone mentioned that the automatic ECU's have a slightly more conservative tune, as opposed to the manual ones. True or false?

4. Is there any advantage whatsoever to running the correct redtop/blacktop ECU specific to the motor? Or are the 62 and E5, and 63 and E6 ECU's identical, when it comes to controlling the motor?

5. Are there any other differences, or advantages/disadvantages that any of them would have over the other? No matter how small or insignificant. I am just curious.


Thank you for your patience.

[Rag]

This also interests me.

[GroundPerformance]

1. Does the fat O2 sensor have any advantage over the skinny one, or vice versa? Are there any differences at all, other than physical?
Only Physical differences.. Same range.

2. Is it true that the auto ECU's do not have a speed limiter? If true, does that mean they are also missing a rev limiter, or do they still have that?
No Speed Limiter but all have Rev Limit.

3. When searching, I read a post where someone mentioned that the automatic ECU's have a slightly more conservative tune, as opposed to the manual ones. True or false?
I haven't seen it but I bet the difference is very minimal to even be an issue.

4. Is there any advantage whatsoever to running the correct redtop/blacktop ECU specific to the motor? Or are the 62 and E5, and 63 and E6 ECU's identical, when it comes to controlling the motor?
NO. Use whatever you can get that works. Only main thing is dealing with CEL codes when using Auto but doesn't affect controlling or perfomance of the motor.

5. Are there any other differences, or advantages/disadvantages that any of them would have over the other? No matter how small or insignificant. I am just curious.
NONE.. Tuning difference might very minimal to make a huge difference.

Thank you for your patience.

This is how I understand it.. Hope it helps!

[Matej]

Thank you, your answer has been most helpful.

I was mainly worried about the auto ECU's not having the rev limiter. I can get a couple locally, but that kept me away. However, if they indeed do have the rev limiter, that is swell.

[KiLLeR2001]

Redtop skinny O2 sensors are Titania based. Fat type blacktop O2 sensors are Zirconia. Depending on what ECU you choose, you need to choose the corresponding O2 sensor.

Look at the differences of Titania vs Zirconia oxygen sensors on google.

Titania = variable resistance
Zirconia = produces voltage

[Matej]

Can anyone confirm that blacktop S13 SR's equipped with an E5/E6 ECU used a 52F00 MAF instead of the 50F00 as I previously assumed?

[GroundPerformance]

Can anyone confirm that blacktop S13 SR's equipped with an E5/E6 ECU used a 52F00 MAF instead of the 50F00 as I previously assumed?

I'm fairly sure that they all use the 52F00 MAF Sensor. 50F00 is the part number for the ECU.. Below is a good link with part numbers for MAF, ECU and others. GL!

Part Numbers! (http://www.240sxmotoring.com/partnumbers.html)