Which sr do I have?

[Harold]

Forgive me if this is noobish but the attached image is a pic of my sr swap currently struggling with wiring issues. Anywho correct me if I'm wrong but is this not a s14 blacktop? I ordered a s13 red top. they sent me this. Has j4 ecu which has a sticker on it saying must be e5.

[jr_ss]

S13 blacktop?

[VNG704]

well, it's got an s13 blacktop head, definitely not an s14. Whether it's originally a chuki or kouki s13, dunno. J4 ecu for kouki and e5 for chuki.

[brndck]

Has j4 ecu which has a sticker on it saying must be e5.

The FUCK did you just say??? Please clarify, using English.

[skyline_guy777]

Looks to be a Red top s13 sr20det painted black, I can't see if the block has the fins on it, if it does then it is a black top sr20det

[jorge1190]

J4 ECU is for the Kouki S13 SR20 and is probably why you are having issues. Find an SR20 ECU wit either E4,E5, 62,63, any of those will work with a non Kouki S13 SR20.

This is assuming you have a harness that is wired for a non Kouki S13 SR with a J4/J5 ECU.

[Mikester]

I don't see fins- looks like a redtop head w/black valve cover as stated above.

Check the O2 sensor- If it's fat and has 3 wires (?) then it's a blacktop... If think with either one or two wires, then it's a redtop.

Either way, I don't think that J4 ECU is the right one for you.

[1990 sr hatch]

Blacktop ecu =e5
Redtop ecu =63

[Harold]

Yeah I have 3 going to the o2

[Harold]

And there are fins on the front of the head so is this ecu and harness the right one for me?

[1990 sr hatch]

If theres fins on the head its a blacktop, you'll need a e5 ecu and harness to match it

[Mikester]

^^Not necessarily. If it's a Koui blacktop, the J4 ECU will run it fine.

S13 SR20DET to S13 240sx Wiring Harness | Wiring Specialties (http://www.wiringspecialties.com/s13srins13241.html)

May be worth a call to these guys. Yury knows his stuff & may know how you can tell whether or not your ECU is correct for your harness & motorset...

[Harold]

I so wish I could afford that. I'm gonna see if I can't do the wiring before I result to that. My head is about to explode over this.

[Harold]

Any Tennessee guys out there willing to help out?

[TheRealSy90]

He said call em and ask for help not buy the harnesses...

[Kingtal0n]

Some redtops in 1991-1992 got the fins on the head.

The ECU has to match the harness- not the engine.

IF it runs on all four cylinders and it has a E5 or 62 ecu then the harness is from a 1989-1996 S13 engine.
Sometime around 97-98 they start making the J4 ecu, for the S13 blacktop engine. The harness is slightly different. IF you google "J4 to 62" I did a write up about how to convert the harness over.