B20A with a OBD1 ECU

[carotman]

I just thought about something yesterday.

Our distributors/crank sensors are OBD-0. This means they will not work with a ODB-1 ECU... However, the B21A (Prelude SR 90-91) used an OBD1 ECU. This means the distributor/crank sensor from the B21A can be bolted to our engines... so we can use any OBD1 ECU.

The P14 came to my mind (Prelude SR 92-96)
This ECU drives the H23A. The fuel maps might be a bit odd but we'll have to try it. It has the advantage to use a knock sensor AND the dual runners...

In fact any non vtec OBD-1 ecu could be used I think.

Anyone tried that?

[Gregg86DX]

If you check out the 3rd Generation Forum over at www.preludepower.com, they talk about converting earlier OBD-0 cars to OBD-1 using the B21 parts. I would guess our conversion would be similar. Looks like you need an ECU harness adapter and might have to futz around with the O2 sensors.

Gregg

[RobT5580]

I will be converting mine and using a AEM EMS most likely. One thing i noticed which is odd for a OBD-0 engine i guess is that the B20A has a 24 tooth distributor gear which is normally 16 teeth for OBD-0. So my plan is to use this distributor if possible with the EMS and a OBD-0 to OBD-1 conversion harness.

And as far as this conversion for a N/A B20A i would rather just use a SAFC and have it dyno tuned it will be easier and probably cheaper.

[carotman]

Hmmmm since it has 24 teeth, do you think it would work with the PK2 ECU from the 88-89 2.0SI lude? (that's the one I was planning to use).

I could just use the lude stuff but I already have the jdm parts so.....

[b20a86lude]

yes it will work carotman see my friend has 3 88-91 distrubutors and i opened up all 3 and counted them just to make postive sure they have 24 teeth ``100 percent sure im happy to cause im using the dist for my jdm b20a ecu

[carotman]

Well, just as an update, the Accord and Prelude B20A use an obd-1 distributor on an obd-0 car... this is somekind of an hybrid setup. This meand we can use a OBD-1 ECU without changing our distributor...

[RobT5580]

Yeah, This is why they have 24 teeth (i think) vs OBD-0 use a 16 tooth trigger wheel. Im going to use my B20A one with the AEM EMS and the only extra work should be in the wiring since the ICM wiring is differnt.