Dohc ecu work on an Sohc?
Dohc ecu work on an Sohc?
I have a Dohc ecu that i know works and was wondering if it would work on the sohc motor? Would it fry things if i plugged it in and tried to start teh car? it has the exact same amount of pins and the harness does plug in. any help would be great thanks.
-
deviousKA
- Posts: 1355
- Joined: Tue Aug 12, 2003 5:04 pm
- Car: 90 240sx NA /72 Datsun 510 NA /86 corolla GTS NA
- Contact:
Re: Dohc ecu work on an Sohc? (madizmo)
It will plug in and start your car. You should swap the dohc maf over though.
The only difference is the sohc harness lacks a knock sensor, and the iat sensor currently in the airbox of your sohc will feed into the dohc egt temp.
You will throw some codes, wiring is the same but some sensors out of spec (like the iat, egt/egr sensors). The sohc lacks the secondary egt sensor.
Your cluster will work, including tach.
But, the sohc ecu is better, particularly, the 90-92 stanza.
The only difference is the sohc harness lacks a knock sensor, and the iat sensor currently in the airbox of your sohc will feed into the dohc egt temp.
You will throw some codes, wiring is the same but some sensors out of spec (like the iat, egt/egr sensors). The sohc lacks the secondary egt sensor.
Your cluster will work, including tach.
But, the sohc ecu is better, particularly, the 90-92 stanza.
Re: (S13 240SX)
Read Devious' post again. It will throw codes, sensors will be out of spec. Its not a direct plug and play, you will need to rewire it. So, the first person that told you 'no' was not lying. Its a lot of work to make it work properly. Just go with the SOHC ECU, or you will have to rewire a lot of it.
-
deviousKA
- Posts: 1355
- Joined: Tue Aug 12, 2003 5:04 pm
- Car: 90 240sx NA /72 Datsun 510 NA /86 corolla GTS NA
- Contact:
There is no reason to run a dohc ecu on a sohc, unless you just like to see how things work (Ive done it). Ive used a ka24de dohc ecu to run a d21 hardbody, p10 g20, and a 90 stanza. And on the flip side ive used a stanza ecu to run a d21, and a p10 g20 also. All of the obd1 nissan 4cyl ecus are compatible wiring wise (90%), and can be interchanged with appropriate rom tuning.
But doing some slight rewiring to run a sohc ecu on a dohc obd1 car (91-94) could be considered worthwhile. This is because the ecu has a lot more tricks under its shell, ones that are easy to figure out.
You can maptrace your fuel/ignition maps in real time with a sohc ecu. This is DIRECT maptracing, not a formulated trace like bikirom does with the dohc 16bit ecus. Instead of taking various sensor input and then deriving a formula to come up with a TP load factor on a computer (slow, inaccurate), on a sohc you just read that final calculated load factor straight from the ecu!
So, like in datascan where you see that cool maptracer that you cant usually use with anything besides a z32. Well you can use it with sohc ka24e ecu as well, in exactly the same way. It works very well and is tremendously useful while ecu tuning, takes 1/3rd the time to reconfigure your maps..
Ok anyways I wasnt real clear in the post above btw,
Differences:
ka24de obd1 ecu - 2 egt circuits, 1 knock circuit
ka24e obd1 ecu - 1 egt circuit, 1 iat circuit (dedicated)
1 of the ka24e egt pinned same as ka24de, the iat (intake air temp) sensor on the ka24e is in the place of the second egt on ka24de.
The ka24e harness lacks the knock sensor and wiring, this pin of the harness connector is blank. You can rob a pin from another harness connector to add knock wiring to sohc harness.
Distributors, coils, power supply, most sensors are all wired the same and compatible between the 89-90 and 91-94.
Same thing goes for altimas, sentras, g20's etc..
Ecus must be used with proper injectors and MAF unless that ecu has been rom tuned for alternate compatibility.
But doing some slight rewiring to run a sohc ecu on a dohc obd1 car (91-94) could be considered worthwhile. This is because the ecu has a lot more tricks under its shell, ones that are easy to figure out.
You can maptrace your fuel/ignition maps in real time with a sohc ecu. This is DIRECT maptracing, not a formulated trace like bikirom does with the dohc 16bit ecus. Instead of taking various sensor input and then deriving a formula to come up with a TP load factor on a computer (slow, inaccurate), on a sohc you just read that final calculated load factor straight from the ecu!
So, like in datascan where you see that cool maptracer that you cant usually use with anything besides a z32. Well you can use it with sohc ka24e ecu as well, in exactly the same way. It works very well and is tremendously useful while ecu tuning, takes 1/3rd the time to reconfigure your maps..
Ok anyways I wasnt real clear in the post above btw,
Differences:
ka24de obd1 ecu - 2 egt circuits, 1 knock circuit
ka24e obd1 ecu - 1 egt circuit, 1 iat circuit (dedicated)
1 of the ka24e egt pinned same as ka24de, the iat (intake air temp) sensor on the ka24e is in the place of the second egt on ka24de.
The ka24e harness lacks the knock sensor and wiring, this pin of the harness connector is blank. You can rob a pin from another harness connector to add knock wiring to sohc harness.
Distributors, coils, power supply, most sensors are all wired the same and compatible between the 89-90 and 91-94.
Same thing goes for altimas, sentras, g20's etc..
Ecus must be used with proper injectors and MAF unless that ecu has been rom tuned for alternate compatibility.
-
deviousKA
- Posts: 1355
- Joined: Tue Aug 12, 2003 5:04 pm
- Car: 90 240sx NA /72 Datsun 510 NA /86 corolla GTS NA
- Contact:
Re: (deviousKA)
Forgot to mention that the iat sensor of the ka24e can monitored and logged completely seperate of the maf.
the ka24de does not offer this feature.
the ka24de does not offer this feature.