Honda swap ?'s

Shift518 Automotive
1

One of my friends is trying to finish up his swap.
The ECU was stolen among other things while the car was in storage.
Instead of replacing the ECU, he bought a Hondata s300 equipped ECU

  • After looking over the car, my best guess was that the map that he loaded
    to the s300 was no good. Idle was perfect, but I didn’t want to drive the car
    with less than perfect timing etc
  • '00 Civic Si
  • HMotors B18c (OBD2a)
  • Civic EX (w/vtec) wiring-harness
  • STOCK with ITR exhaust
  • Hondata s300 ECU with jumper (OBD2 to OBD1)

Should we run the EX harness to a new p72 and be running smoothly?

2

Yea as long as you have a vtec harness it should be fine

3

Load another map, hondata offers a bunch of base maps

4

You should just get the OBDII P72 and be done with it. Without having additional modifications, there is very little (if any) to be gained from a chipped ECU. If you were running boost, the story changes obviously. If you want to use an OBDI ecu with an OBDII B18c you need to change the IAB wiring as OBDI ecu will apply ground and OBDII ecu will apply power in order to activate the IAB solenoid. Otherwise you could just forget about the IAB setup and not have the midrange power increase that comes with it working.

5

Thought so, glad I asked though

I was thinking about doing this for him…He has a brand new PLX Wideband too we could use if he keeps the s300 vs stock ecu

I think that’s what we are going to do for now. Just get the stock ECU, and down the road
swap in the jumper/s300/wideband/tune. No point in it now, being bone stock etc. but Im looking for a OBDII P72 so we
get the IAB.

6

Car = OBD2A
Motor = OBD2B

So I need an OBD2B P72 correct?

7

Stick with whatever the car is wired for as the connectors are different at the ECU.

8

wouldnt the car be an obd2B since it’s an 00?

9

Actually, now that I think about it… run an OBDIIa ECU. You don’t want to run into immobilizer issues here…

10

Yea, but the engine harness would really determine that. It looks like the wiring harness is from a different vehicle, so if its wired for OBDIIa he should get the OBDIIa ECU. Regardless, the immobilizer is a pain in the balls so I would avoid it without the correct wiring and sensors on the motor side of things.

11

You would need an obd2b for that car

12

I would still do OBDIIa with a jumper harness if it’s wired for B. Fuck the immobilizer.

13

Quoted for the truth.

14

Thanks man, now Ive just got to find one to borrow for a minute

Not trying to buy another jumper to go B to A…if its the only remaining option, maybe
Is there a way to bypass the immobilizer? Ive seen “mobilizer” chips for sale, but Im
hoping there is a better way.

Thinking about just loading a new map on the Hondata at this point

15

If you want a CEL to be on 24/7 you can bypass it, otherwise I don’t know of any real fix besides running OBDIIa.

16

I thought all cars 99 and up were obd2b

17

there was a how-to on honda-tech a while back. you take out the circuit and replace it with a specific transistor.

18

So, its looking like a reflash to the Hondata…